This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 11251. |
If 3a = 4b = 6c and a + b + c = \(27\sqrt{29}\) , then \(\sqrt{a^2+b^2+c^2}\) is(a) \(3\sqrt{29}\) (b) 81(c) 87(d) 29 |
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Answer» (c) 87 3a = 4b = 6c \(\Rightarrow\) 4b = 6c \(\Rightarrow\) b = \(\frac{3}{2}c\) and 3a = 4b \(\Rightarrow\) a = \(\frac{4}{3}b\) = \(\frac{4}{3}\times \frac{3}{2}c\) = 2c \(\therefore\) a + b + c = \(27\sqrt{29}\) \(\Rightarrow\) 2c + \(\frac{3}{2}c\) + c = \(27\sqrt{29}\) \(\Rightarrow\) \(\frac{9}{2}c\) = \(27\sqrt{29}\) \(\Rightarrow\) c = \(6\sqrt{29}\) Now, \(\sqrt{a^2+b^2+c^2}\) = \(\sqrt{(a+b+c)^2-2(ab+bc+ca)}\) = \(\sqrt{(27\sqrt{29})^2-2(2c\times\frac{3}{2}c+\frac{3}{2}c\times c+c\times 2c)}\) = \(\sqrt{729 \times29 - 2(3c^2+\frac{3}{2}c^2+2c^2})\) = \(\sqrt{729 \times29 - 2\times \frac{13c^2}{2}}\) = \(\sqrt{729 \times29 - 13\times(6\sqrt{29)^2}}\) = \(\sqrt{29(729-468)}\) = \(\sqrt{29\times261}\) = \(\sqrt{29\times29\times9}\) =29 x 3 = 87 |
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| 11252. |
Find the square root of 9216 by using the method of prime factorization. |
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Answer» By resolving given number into prime factors, we get 9216 = 2 × 2 × 2 × 2 × 2 × 2 × 2 × 2 × 2 × 2 × 3 × 3 Therefore, \(\sqrt{9216}\) = 2 × 2 × 2 × 2 × 2 × 3 = 96 |
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| 11253. |
Evaluate:√(16/81) |
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Answer» Given √(16/81) We can write it as √(16/81) = √16/√81 But we know that √16=4 and √81=9 By substituting the values we get √(16/81) = 4/9 |
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| 11254. |
Find the square root of 225 by using the method of prime factorization. |
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Answer» By using prime factorization method, we get 225 = 3 × 3 × 5 × 5 \(\sqrt{225}\) = 3 × 5 = 15 |
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| 11255. |
Find the square roots of 121 and 169 by the method of repeated subtraction. |
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Answer» We find the square roots of 121 and 169 by the method of repeated subtraction 121 – 1 = 120 120 – 3 = 117 117 – 5 = 112 112 – 7 = 115 115 – 9 = 106 106 – 11 = 95 95 – 13 = 82 82 – 15 = 67 67 – 17 = 50 50 – 19 = 31 31 – 21 = 10 Hence, we have performed operation 11 times. Now, ∴ √121 = 11 169 – 1 = 168 168 – 3 = 165 165 – 5 = 160 160 – 7 = 153 153 – 9 = 144 144 – 11 = 133 133 – 13 = 120 120 – 15 = 105 105 – 17 = 88 88 – 19 = 69 69 – 21 = 48 48 – 23 = 25 25 – 25 = 0 Clearly, we have performed subtraction 13 times ∴ √169 = 13 |
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| 11256. |
Evaluate:√(64/225) |
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Answer» Given √(64/225) We can write it as √(64/225) = √64/√225 But we know that √64=8 and √225=15 By substituting the values we get √(64/225) =8/15 |
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| 11257. |
Evaluate:√(121/256) |
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Answer» Given √(121/256) We can write it as √(121/256) = √121/√226 But we know that √121=11 and √256=16 By substituting the values we get √ (121/256) =11/16 |
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| 11258. |
Find the square root of: (i) 23394/729(ii) 2151/169(iii) 10151/225 |
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Answer» (i) \(23\frac{394}{729}\) √(23394/729) = √(17161/729) = \(4\frac{23}{27}\) (ii) \(21\frac{51}{169}\) = \(\sqrt{21\frac{51}{169}}\) = √(3600/169) = 60/13 = \(4\frac{8}{13}\) (iii) \(10\frac{151}{225}\) = \(\sqrt{10\frac{151}{225}}\) = √(2401/225) = 49/15 = \(3\frac{4}{15}\) |
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| 11259. |
The area of a square field is \(80\frac{244}{729}\) square metres. Find the length of each side of the field. |
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Answer» The given area = \(80\frac{244}{729}\) m2 = 58564/729 m2 If L is length of each side L2 = 58564/729 L = √ (58564/729) = √58564/√729 = 242/27 = \(8\frac{26}{27}\) Hence, Length is \(8\frac{26}{27}\) |
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| 11260. |
Evaluate:√(3 (13/36)) |
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Answer» Given √(3(13/36)) Converting the given fraction into improper we get √(121/36) We can write it as √(121/36) = √121/√36 But we know that √36=6 and √121=11 By substituting the values we get √(121/36) =11/6 |
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| 11261. |
Evaluate:√(625/729) |
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Answer» Given √(625/729) We can write it as √(625/729) = √625/√729 But we know that √625=25 and √729=27 By substituting the values we get √ (625/729) =25/27 |
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| 11262. |
Write the truth value (T/F) of each of the following statements: (i) Two lines intersect in a point. (ii) Two lines may intersect in two points. (iii) A segment has no length. (iv) Two distinct points always determine a line. (v) Every ray has a finite length. (vi) A ray has one end-point only. (vii) A segment has one end-point only. (viii) The ray AB is same as ray BA. (ix) Only a single line may pass through a given point. (x) Two lines are coincident if they have only one point in common. |
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Answer» (i) False (ii) False (iii) False (iv) True (v) False (vi) True (vii) False (viii) False (ix) False (x) False |
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| 11263. |
Three pipes A, B and C can fill a tank in 6 min., 8 min, and 12 min. respectively. The pipe C is closed for 4 min before the tank is filled. In what time would the tank be fill? |
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Answer» Let the tank be full in x min. Then, \(\frac{X}{6}+\frac{X}{8}\) + \(\frac{X-4}{12}\) = 1 \(\Rightarrow\) \(\frac{4X+3X+2(X-4)}{24}\) = 1 \(\Rightarrow\) 9x – 8 = 24 \(\Rightarrow\) 9x = 32 \(\Rightarrow\) x = \(3\frac{5}{9}\) min |
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| 11264. |
Three pipes A, B and C can fill a tank in 6 hours. After working at it together for 2 hours, C is closed and A and B can fill the remaining part in 7 hours. The number of hours taken by C alone to fill the tank is (a) 10(b) 12 (c) 14 (d) 16 |
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Answer» (c) 14 Part of the tank filled by (A + B + C) in 2 hours = 2 x \(\frac{1}{6}\) = \(\frac{1}{3}\) Remaining part = 1 - \(\frac{1}{3}\) = \(\frac{2}{3}\) \(\therefore\) \(\frac{2}{3}\)rd of the tank is filled by (A + B) in 7 hours. \(\therefore\) The whole tank is filled by (A + B) in \(\big(7\times\frac{3}{2}\big)\) hours = \(\frac{21}{2}\) hours \(\therefore\) Part of the tank filled by C in 1 hour = Part of the tank filled by (A + B + C) in 1 hour - Part of the tank filled by (A + B) in 1 hour = \(\frac{1}{6}\) - \(\frac{2}{21}\) = \(\frac{3}{42}\) = \(\frac{1}{14}\) \(\therefore\) C can fill the whole tank in 14 hours. |
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| 11265. |
Pipes A, B and C are attached to a cistern. A and B can fill it in 20 min and 30 min respectively, while C can empty it in 15 min. If A, B and C are kept in operation successively for 1 minute each, how soon will the cistern be filled? (a) 167 min (b) 160 min (c) 166 min (d) 164 min |
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Answer» (a) 167 min Work done in 3 min. = \(\big(\frac{1}{20}+\frac{1}{30}-\frac{1}{15}\big)\) = \(\frac{1}{60}\) \(\therefore\) Work done in 3 × 55 = 165 min = \(\frac{55}{60}\) \(\therefore\) Remaining tank = \(\big(1-\frac{55}{60}\big)\) = \(\frac{5}{60}\) = \(\frac{1}{12}\) Now its A’s turn, \(\frac{1}{20}\) part of the tank is filled by A in 1 min. Since there is still \(\big(\frac{1}{12}-\frac{1}{20}\big)\) = \(\frac{1}{30}\) tank to be filled, which will be filled by B in 1 min. Therefore, required time = (165 + 2) = 167 min. |
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| 11266. |
If two pipes are put in operation simultaneously, the tank is filled in 24 min. One pipe fills the tank in 20 min faster than the other. How many hours does the faster pipe take to fill the tank? (a) 60 min (b) 45 min (c) 40 min (d) 30 min |
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Answer» (c) 40 min Let one pipe take x minutes to fill the tank, then the other will take (x + 20) minutes. Given, \(\frac{1}{X}+\frac{1}{X+20}\) = \(\frac{1}{24}\) \(\Rightarrow\) \(\frac{X+20+X}{X^2+20X}\)= \(\frac{1}{24}\) \(\Rightarrow\) (2x + 20)24 = x2 + 20x \(\Rightarrow\) x2 – 28x – 480 = 0 \(\Rightarrow\) x 2 – 40x + 12x – 480 = 0 \(\Rightarrow\) x(x – 40) + 12(x – 40) = 0 \(\Rightarrow\) (x – 40) (x +12) = 0 \(\Rightarrow\) x = 40 or –12 Neglecting negative values x = 40 min |
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| 11267. |
Two pipes A and B can fill a water tank in 20 minutes and 24 minutes respectively and the third pipe C can empty at the rate of 3 gallons per minute. If A, B and C opened together fill the tank in 15 minutes, the capacity (in gallons) of the tank is (a) 180 (b) 150 (c) 120 (d) 60 |
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Answer» Part of the tank filled when all the three pipes are opened in 1 minute = \(\frac{1}{15}\) Part of the tank filled when (A + B) are opened in 1 minute = \(\frac{1}{20}\)+\(\frac{1}{24}\)= \(\frac{6+5}{120}\) = \(\frac{11}{120}\) \(\therefore\) Part of the tank emptied by C in 1 min. = \(\frac{11}{120}\) - \(\frac{1}{15}\) = \(\frac{1}{40}\) \(\therefore\) Capacity of \(\frac{1}{40}\) part of the tank = 3 gallons \(\therefore\) Capacity of the tank = (3 × 40) gallons = 120 gallons. |
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| 11268. |
Two pipes A and B can fill a cistern in 20 min and 25 min respectively. Both the pipes are opened together but at the end of 5 min, the first is turned off. How long does it take to fill the cistern? |
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Answer» Let it take x minutes to fill the cistern, then work done by (Pipe A in 5 min. + Pipe B in x min.) = 1 \(\Rightarrow\) \(\frac{5}{20}\)+ \(\frac{X}{25}\)= 1 \(\Rightarrow\) \(\frac{25+4X}{100}\) = 1 \(\Rightarrow\) 25 + 4x = 100 \(\Rightarrow\) 4x = 75 \(\Rightarrow\)x = 18.75 min |
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| 11269. |
A large tanker can be filled by two pipes A and B in 60 minutes and 40 minutes respectively. How many minutes will it take to fill the tanker from empty state if B is used for half the time and A and B fill it for the other half? (a) 15 minutes (b) 20 minutes (c) 27.5 minutes (d) 30 minutes |
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Answer» (d) 30 minutes Let the total time taken to fill the tank be x minutes.Then, work by B in half hour + work done by (A + B) in half hour = 1 \(\big(\frac{1}{40}\times\frac{X}{2}\big)\) + \(\big(\frac{1}{60}+\frac{1}{40}\big)\) x \(\frac{X}{2}\) = 1 \(\Rightarrow\) \(\frac{X}{80}\) + \(\frac{X}{48}\) = 1 \(\Rightarrow\) \(\frac{3X+5X}{240}\) = 1 \(\Rightarrow\) 8x = 240 \(\Rightarrow\) x = 30 min. |
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| 11270. |
Two pipes A and B can fill a cistern in 12 min and 16 min respectively. Both the pipes are opened together for a certain time but due to some obstruction, the flow of water was restricted to \(\frac{7}{8}\) of the full flow in pipe A and \(\frac{5}{6}\) of the full in pipe B. The obstruction, is removed after some time and the tank is now filled in 3 min from that moment. For how many minutes was the obstruction there? (a) 8 min (b) 3 min (c) 5.6 min (d) 4.5 min |
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Answer» (d) 4.5 min Let the obstruction remain for x minutes only \(\therefore\) Part of cistern filled in x minutes + Part of cistern filled in 3 minutes = cistern filled \(\Big[\big(\frac{7}{8}\times\frac{X}{12}\big)+\big(\frac{5}{6}\times\frac{X}{16}\big)\Big]\) + \(\Big[\frac{3}{12}+\frac{3}{16}\Big]\) = 1 \(\Rightarrow\) \(\frac{12X}{96}\) + \(\frac{7}{16}\) = 1 \(\Rightarrow\) \(\frac{12X}{96}\) = \(\frac{9}{16}\) \(\Rightarrow\) x = \(\frac{9\times96}{16\times12}\) = 4.5 min |
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| 11271. |
How many part of the tank will be empty in 1 hour, if an outlet empties a full tank in m hours? |
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Answer» If an outlet empties a full tank in m hours, then it will empty \(\frac{1}{m}\)th part of the tank in 1 hour, i.e., work done by it is \(-\frac{1}{m}\). |
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| 11272. |
Two pipes can fill a tank in 20 minutes,end 30 minutes respectively. If both the pipes are opened simultaneously then the lank will he filled A. 10 minutes B. 12 minutes C. 15 minutes D. 25 minutes |
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Answer» Number of minutes Pipe A requires to fill an empty tank : 20 minutes Number of minutes Pipe B requires to fill an empty tank : 30 minutes Amount of water filled by Pipe A in empty tank in one minute: \(\frac{1}{20}\) Amount of water filled by Pipe B in one minute: \(\frac{1}{30}\) Amount of water filled by Pipe A and Pipe B together in one minute: \(\frac{1}{20}+\frac{1}{30}=\frac{5}{60}=\frac{1}{12}\) ∴ They can fill the tank together in 12 minutes. |
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| 11273. |
A tap can fill a tank in 16 minutes and another can empty it in 8 minutes. If the tank is already \(\frac{1}{2}\) full and both the taps are opened together, will the tank be filled or emptied? How long will it take before the tank is either filled completely or emptied completely, as the case may be? |
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Answer» In one minute, \(\frac{1}{16}\) - \(\frac{1}{8}\) = - \(\frac{1}{16}\) of the tank can be filled, i.e.,\(\frac{1}{16}\) of the whole tank can be emptied. \(\therefore\) The whole tank can be emptied in 16 minutes. Since the tank is half full, therefore it will be emptied in 8 minutes. |
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| 11274. |
Two taps can fill a tank in 20 minutes and 30 minutes respectively. There is an outlet tap at exactly half level of that rectangular tank which can pump out 100 litres of water per minute. If the outlet tap is open, then it takes 24 minutes to fill an empty tank. What is the volume of the tank? (a) 1800 litres (b) 1500 litres (c) 1200 litres (d) 2400 litres |
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Answer» (a) 1800 litres Part of the tank that can be filled by the two filler taps = \(\big(\frac{1}{30}+\frac{1}{20}\big)\) = \(\frac{2+3}{60}\) = \(\frac{5}{60}\) = \(\frac{1}{12}\) \(\therefore\) The two taps can fill the tank in 12 minutes. \(\Rightarrow\) Half of the tank will be filled in 6 minutes \(\Rightarrow\) The time taken by the remaining half of the tank to be filled when the outlet pipe is open = (24 – 6) min = 18 min. \(\Rightarrow\) Part of that half of the tank that can be emptied in 1 hour = \(\frac{1}{6}\) - \(\frac{1}{18}\) = \(\frac{1}{9}\) \(\therefore\) Time taken to empty half of the cistern = 9 minutes \(\therefore\) Capacity of the tank = 100 × 9 × 2 = 1800 litres. |
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| 11275. |
Pipes A and B can fill an empty tank in 10 hours and 15 hours respectively. If both are opened together in the empty tank, how much time will they take to fill it completely? |
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Answer» Number of hours Pipe A requires to fill an empty tank : 10 hours Number of hours Pipe B requires to fill an empty tank : 15 hours Amount of water filled by Pipe A in empty tank in one hour: \(\frac{1}{10}\) Amount of water filled by Pipe B in one hour: \(\frac{1}{15}\) Amount of water filled by Pipe A and Pipe B together in one hour: \(\frac{1}{10}+\frac{1}{15}=\frac{5}{30}=\frac{1}{6}\) ∴ They can fill the tank together in 6 hours. |
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| 11276. |
The rates of working of A and B are in the ratio 3 : 4. The number of days taken by them to finish the work are in the ratio A. 3 : 4 B. 9 16 C. 4: 3 D. 16 : 9 |
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Answer» We know that number of days taken to work is reciprocal of the rate of the work. ∴ Work done by A: \(\frac{1}{3}\) Work done by B: \(\frac{1}{4}\) ∴ Ratio of work done is \(\frac{1}{3}:\frac{1}{4}=4:3\) |
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| 11277. |
Rs 53 are divided among A, B and C such that A gets Rs 7 more than B and B gets Rs 8 more than C. What is the ratio of their shares ? (a) 16 : 9 : 18 (b) 25 : 18 : 10 (c) 18 : 25 : 10 (d) 15 : 8 : 30 |
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Answer» (b) 25 : 18 : 10 Given, A + B + C = 53 … (i) Also, A = B + 7 and B = C + 8 ∴ From (i), we get (B + 7) + B + (B – 8) = 53 ⇒ 3B = 54 ⇒ B = 18 ⇒ A = 25 and C = 10 ∴ A : B : C = 25 : 18 : 10 |
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| 11278. |
A cistern has two inlets A and B which can fill it in 12 hours and 15 hours respectively. An outlet can empty the full cistern in 10 hours. If all the three pipes are opened together in the empty cistern, how much time will they take to fill the cistern completely? |
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Answer» Given, Inlet A can fill the cistern in = 12 hours Inlet B can fill it in = 15 hours Outlet pipe can empty it in = 10 hours ∵ Work done by pipe A in 1 hour \(=\frac{1}{12}\) ∵ Work done by pipe B in 1 hour =\(\frac{1}{15}\) ∵ work done by outlet pipe in 1 hour \(=\frac{1}{10}\) ∴ Net work done by 3 pipe in 1 hour \(=[{\frac{1}{12}+\frac{1}{15}}]-\frac{1}{10}=\frac{9}{60}-\frac{1}{10}=\frac{9-6}{60}=\frac{3}{60}=\frac{1}{20}\)part Hence, time taken by 3 pipes to fill the tank \(=\frac{1}{\frac{1}{20}}\)= 20 hours |
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| 11279. |
Two taps A and B can fill an overhead tank in 10 hours and 15 hours respectively. Both the taps are opened for 4 hours and then B is turned off. How much time will A take to fill the remaining tank? |
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Answer» Given, Tap A can fill a tank in= 10 hours Tap B can fill the tank in = 15 hours Work done by Tap A in 1 hour \(\frac{1}{10}\) Work done by tap B in 1 hour \(=\frac{1}{15}\) ∴ Work done by both tap in 1 hour \(=\frac{1}{10}+\frac{1}{15}=\frac{3+2}{30}=\frac{5}{30}=\frac{1}{6}\)part Work done by both tap in 4 hours \(={4}\times\frac{1}{6}=\frac{2}{3}\)part Remaining part \(={1}-\frac{2}{3}=\frac{1}{3}\)part Hence, time taken by A to fill remaining part \(=\frac{\frac{1}{3}}{\frac{1}{10}}=\frac{10}{3}={3}\frac{1}{3}\)hours |
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| 11280. |
Working 8 hours a day, Ashu can copy a book in 18 days. How many hours a day should he work so as to finish the work in 12 days? |
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Answer» ∵Working 8 hours a day Ashu can complete a work in = 18 days ∴ Working 1 hours a day he can complete it in = 18 × 8 = 144 days ∴ Number of hours he should work to complete the work in 12 days \(=\frac{144}{12}\)=12 hours/day |
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| 11281. |
15 men, 18 women and 12 boys working together earned Rs 2070. If the daily wages of a man, a woman and a boy are in the ratio 4 : 3 : 2, the daily wages (in Rs) of 1 man, 2 women and 3 boys are (a)135 (b) 180 (c)240 (d) 205 |
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Answer» (c) Rs 240 Suppose the daily wages of a man, a woman and a boy are 4k, 3k and 2k respectively. ∴ 15 x 4k + 18 x 3k + 12 x 2k = 2070 ⇒ 60k + 54k + 24k = 2070 ⇒ 138k = 2070 ⇒ k = 15. ∴ Daily wages of a man, a woman and a boy are Rs 60, Rs 45 ∴ Daily wages of 1 man + 2 women + 3 boys = Rs 60 + 2 × Rs 45 + 3 × Rs 30 = Rs 60 + Rs 90 + Rs 90 = Rs 240 |
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| 11282. |
A pipe can fill a cistern in 10 hours. Due to a leak in the bottom it is filled in 12 hours. When the cistern is full, in how much time will it be emptied by the leak? |
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Answer» Given, A pipe can fill a cistern in = 10 hours Due to leakage it get filled in = 12 hours ∵ Without leakage work done by pipe in 1 hour \(=\frac{1}{10}\)part ∵ With leakage work done by pipe in 1 hour \(=\frac{1}{12}\)part ∴ Work done by leakage in 1 hour =\(\frac{1}{10}-\frac{1}{12}=\frac{12-10}{120}=\frac{2}{120}=\frac{1}{60}\)part Hence, the cistern will be emptied by leakage in \(=\frac{1}{\frac{1}{60}}\)=60 hours. |
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| 11283. |
If 6 persons working 8 hours a day earn Rs 8400 per week, then how much will 9 persons working 6 hours a day each per week? |
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Answer» 6 persons working 8 hours a day earn Rs 8400 in a week 6 persons working 1 hour a day earn Rs \(\frac{8400}{8}\) in a week. \(\therefore\) 1 person working 1 hour a day earns Rs \(\frac{8400}{6\times8}\) in a week. (less persons, less days, less earnings) 1 person working 6 hours a day earns Rs \(\frac{8400\times9\times6}{6\times8}\) in a week. (more persons, more hours, more earning) = Rs 9450. |
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| 11284. |
A cistern has a leak which would empty it in 8 hours. A tap is turned on, which admits 6 litres a minute into the cistern and it is now emptied in 12 hours. How many litres can the cistern hold? (a) 8000 litres (b) 8400 litres (c) 8640 litres (d) 8650 litres |
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Answer» (c) 8640 litres Suppose the cistern holds x litres of water. The tap admits 6 litres of water in 1 minute, i.e., it admits 360 litres of water in 1hour. \(\therefore\) x litres of water can be filled in \(\frac{X}{360}\) hours. The leak would empty the tank in 8 hours. \(\therefore\) In one hour, \(\frac{1}{8}\) of the tank becomes empty. If the tap and the leak both are allowed simultaneously, then the tank becomes empty in 12 hours, i.e., \(\frac{1}{8}-\frac{360}{X}\) = \(\frac{1}{12}\) \(\Rightarrow\) \(\frac{360}{X}\) = \(\frac{1}{8}\) - \(\frac{1}{12}\) = \(\frac{3-2}{24}\) = \(\frac{1}{24}\) \(\Rightarrow\) x = (360 × 24) litres = 8640 litres. |
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| 11285. |
Two pipes A and B can separately fill a cistern in 60 minutes and 75 minutes respectively. There is a third pipe at the bottom of the cistern to empty it. If all the three pipes are simultaneously opened, then the cistern is full in 50 minutes. In how much time, the third pipe alone can empty the cistern? (a) 110 minutes (b) 100 minutes (c) 120 minutes (d) 90 minutes |
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Answer» (b) 100 minutes Let the third pipe empty the whole cistern in x minutes. \(\therefore\) \(\frac{1}{60}+\frac{1}{75}\) - \(\frac{1}{X}\) = \(\frac{1}{50}\) \(\Rightarrow\) \(\frac{1}{X}\) = \(\frac{1}{60}+\frac{1}{75}-\frac{1}{50}\) = \(\frac{5+4-6}{300}\) = \(\frac{3}{300}\) = \(\frac{1}{100}\) The third pipe can empty the cistern in 100 minutes |
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| 11286. |
Tap A can fill a cistern in 8 hours and tap B can empty it in 12 hours. How long will it take to fill the cistern if both of them are opened together? |
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Answer» Number of hours Tap A requires to fill an empty tank : 8 hours Number of hours Tap B requires to empty the full tank : 12 hours Amount of water filled by Tap A in empty tank in one hour: \(\frac{1}{8}\) Amount of water Tap B empties in one hour: \(\frac{1}{12}\) Amount of water filled by Tap A and Tap B together in one hour: \(\frac{1}{8}-\frac{1}{12}=\frac{1}{24}\) ∴ They can fill the tank together in 24 hours. |
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| 11287. |
24 men can complete a piece of work in 16 days and 18 women can complete the same work in 32 days. 12 men and 6 women work together for 16 days. If the remaining work was to be completed in 2 days, how many additional men would be required besides 12 men and 6 women ? |
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Answer» 24 men can complete a work in 16 days \(\therefore\) 1 man’s 1 days’ work = \(\frac{1}{24\times16}\) \(\therefore\) 12 men’s 1 day’s work = \(\frac{12}{24\times16}\) = \(\frac{1}{32}\) 18 women can complete the work in 32 days \(\therefore\) 1 woman’s 1 days’ work = \(\frac{1}{18\times32}\) \(\therefore\) 6 women’s 1 day’s work = \(\frac{6}{18\times32}\) = \(\frac{1}{96}\) \(\therefore\) (12 men’s + 6 women’s) 16 days’ work = 16 x \(\big(\frac{1}{32}+\frac{1}{96}\big)\) = 16 x \(\big(\frac{3+1}{96}\big)\) = 16 x \(\frac{4}{96}\) = \(\frac{2}{3}\) \(\therefore\) Remaining work = 1 - \(\frac{2}{3}\) = \(\frac{1}{3}\) (12 men’s + 6 women’s) 2 days’ work = 2 x \(\big(\frac{1}{32}+\frac{1}{96}\big)\) = 2 x \(\big(\frac{4}{96}\big)\) = \(\frac{1}{12}\) Remaining work = \(\frac{1}{3}\) - \(\frac{1}{12}\) = \(\frac{3}{12}\) = \(\frac{1}{4}\) \(\therefore\) \(\frac{1}{384}\) work is done in 1 day by 1 man \(\therefore\) \(\frac{1}{12}\) work will be done in 2 days by \(\big(384\times\frac{1}{12}\times\frac{1}{2}\big)\)men = 16 men. |
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| 11288. |
The work done by a man, a woman and a child are in the ratio 3 : 2 : 1. If the daily wages of 20 men, 30 women and 36 children amount to Rs 78, what will be the wages of 15 men, 21 women and 30 children for 18 weeks ? (a) Rs 7371 (b) Rs 8645 (c) Rs 9000 (d) Rs 9500 |
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Answer» (a) Rs 7371 Given, Man : Woman : Child = 3 : 2 :1 \(\Rightarrow\) M = 3K , W = 2K, C = K, where K is a constant \(\Rightarrow\) M = 3C , W = 2C \(\therefore\) 20M + 30 W + 36C = 60C + 60C + 36C = 156C and 15M + 21W + 30C = 45C + 42C + 30C = 117C It is given that (20 men + 30 women + 36 children) = 156 children earn Rs 78 per day \(\Rightarrow\) 1 child earns Rs \(\frac{78}{156}\) per day = Rs \(\frac{1}{2}\) per day. \(\therefore\) (15 men + 21 women + 30 children) = 117 children should get \(\big(Rs\, \frac{1}{2}\times117\big)\) per day, i.e., Rs \(\big(\frac{1}{2}\times117\times18\times7\big)\) = Rs 7371 in 18 weeks. |
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| 11289. |
Whose friendship with the cool breeze would be sweet, in ‘If I was a Tree’? |
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Answer» In ‘If I was a Tree’, the friendship of the tree with the cool breeze and the leaves would be sweet. |
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| 11290. |
Twenty four men can complete a work in sixteen days. Thirty two women can complete the same work in twenty four days. Sixteen men and sixteen women started working and worked for 12 days. How many more men are to be added to complete the remaining work in 2 days ? (a) 16 (b) 24 (c) 36 (d) 48 |
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Answer» (b) 24 1 man’s 1 days’ work = \(\frac{1}{24\times16}\) \(\therefore\) 16 men’s 1days’ work = \(\frac{16}{24\times16}\) = \(\frac{1}{24}\) 1 woman’s 1 days’ work = \(\frac{1}{32\times24}\) 16 women’s 1 days’ work = \(\frac{16}{32\times24}\) = \(\frac{1}{48}\) \(\therefore\) 12 days’ work of (16 men + 16 women) = 12\(\big(\frac{1}{24}+\frac{1}{48}\big)\) = 12\(\big(\frac{2+1}{48}\big)\) = 12 x \(\frac{3}{48}\) = \(\frac{3}{4}\) Remaining work = 1 - \(\frac{3}{4}\) = \(\frac{1}{4}\) Now (16 men’s + 16 women’s) 2 days’ work = 2\(\big(\frac{1}{24}+\frac{1}{48}\big)\) = 2 x \(\frac{1}{16}\) = \(\frac{1}{8}\) \(\therefore\) Remaining work = \(\frac{1}{4}\) - \(\frac{1}{8}\) = \(\frac{1}{8}\) \(\frac{1}{384}\) work is done in 1 day by 1 man \(\therefore\) \(\frac{1}{8}\) work will be done in 2 days by \(\big(384\times\frac{1}{8}\times\frac{1}{2}\big)\) = 24 men. |
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| 11291. |
3 men or 5 women can do a work in 12 days. How long will 6 men and 5 women take to do it? A. 6 days B. 5 days C. 4 days D. 3 days |
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Answer» Number of days required by 3 men to finish the work : 12 days Number of days required by 5 women to finish the work : 12 days Number of days required by 1 man to finish the work : 3 x 12 = 36 days Number of days required by 1 woman to finish the work : 5 x 12 = 60 days Work done by a man in one day: \(\frac{1}{36}\) Work done by a woman in one day: \(\frac{1}{60}\) Work done by 6 men in one day: \(6\times\frac{1}{36}=\frac{1}{6}\) Work done by 5 women in one day: \(5\times\frac{1}{60}=\frac{1}{12}\) Work done by 6 men and 5 women together in one day: \(\frac{1}{6}+\frac{1}{12}=\frac{3}{12}=\frac{1}{4}\) ∴ 6 men and 5 women together take 4 days to complete the work. |
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| 11292. |
2 men or 3 women can do a piece of work in 16 days. In how many days can 4 men and 6 women do the same work? |
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Answer» Number of days required by 2 men to finish the work : 16 days Number of days required by 3 women to finish the work : 16 days Number of days required by 1 man to finish the work : 2 x 16 = 32 days Number of days required by 1 woman to finish the work : 3 x 16 = 48 days Work done by a man in one day: \(\frac{1}{32}\) Work done by a woman in one day: \(\frac{1}{48}\) Work done by 4 men in one day: \(4\times\frac{1}{32}=\frac{1}{8}\) Work done by 6 women in one day: \(6\times\frac{1}{48}=\frac{1}{8}\) Work done by 4 men and 6 women together in one day: \(\frac{1}{8}+\frac{1}{8}=\frac{2}{8}=\frac{1}{4}\) ∴ 4 men and 6 women together take 4 days to complete the work. |
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| 11293. |
Three men, four women and six children can complete a work in seven days. A woman does double the work a man does and a child does half the work a man does. How many women alone can complete the work in 7 days ? (a) 7 (b) 8 (c) 14 (d) 12 |
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Answer» (a) 7 Let 1 woman’s 1 days’ work = x. Then 1 man’s 1 days’ work = \(\frac{X}{2}\) and 1 child’s 1 days’ work = \(\frac{X}{4}\) Given, (3 men’s + 4 women’s + 6 children’s) 1 days’ work = \(\frac{1}{7}\) \(\Rightarrow\) \(\frac{3X}{2}\)+ 4x + \(\frac{6X}{4}\) = \(\frac{1}{7}\) \(\Rightarrow\) \(\frac{6X+16X+6X}{4}\) = \(\frac{1}{7}\) \(\Rightarrow\) \(\frac{28X}{4}\) = \(\frac{1}{7}\) \(\Rightarrow\) x = \(\frac{1}{49}\) \(\therefore\) 1 woman can alone complete the work in 49 days To complete the work in 7 days, number of women required = \(\frac{49}{7}\) = 7. |
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| 11294. |
Ten women can complete a piece in 15 days. Six men can complete the same piece of work in 10 days. In how many days can 5 women and six men together complete the piece of work ? (a) 15 days (b) 7.5 days (c) 9 days (d) 12.5 days |
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Answer» (b) 7.5 days 10 women can complete a piece of work in 15 days \(\therefore\) 1 woman can complete in 1 day, \(\frac{1}{10\times15}\) = \(\frac{1}{150}\) part of work 6 men can complete the same work in 10 days, \(\therefore\) 1 man can complete in 1 day, \(\frac{1}{6\times10}\) = \(\frac{1}{60}\) part of the work \(\therefore\) (6 men’s + 5 women’s) 1 days’ work = \(\frac{6}{60}\)+ \(\frac{5}{150}\) = \(\frac{1}{10}\) + \(\frac{1}{30}\) = \(\frac{3+1}{30}\) = \(\frac{4}{30}\) = \(\frac{2}{15}\) \(\therefore\) 6 men and 5 women can complete the whole work in \(\frac{15}{2}\) = 7.5 days |
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| 11295. |
The ........ would embrace the tree in the poem ‘If I was a Tree’(a) cow(b) sunlight(c) bird. |
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Answer» The sunlight would embrace the tree in the poem ‘If I was a Tree’ |
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| 11296. |
How do the life forces – sunlight and the cool breeze – enforce nature’s idea of equality? |
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Answer» The poem ‘If I was a tree’ is a satire in which the poet makes an attempt to expose the subtle ways in which the upper caste society has been discriminating against untouchables for centuries. The speaker juxtaposes the world of nature with the human world so as to accuse human beings of practising untouchability and being meaner than the world of nature. The speaker speaks in the persona of an untouchable but asks the reader to imagine that he is a tree. Next, he presents a few everyday instances of untouchability. In the poem, the tree is a metaphor for the world of nature and, using the tree as the point of contact between nature and the people, he points out how elements of nature like the ‘cool breeze’ and the ‘sunlight’ do not discriminate between people and treat everyone equally. Thus he highlights nature’s idea of equality. The speaker argues that if he was a tree, and when sunlight falls on him, his shadow would not feel defiled. On the contrary, if he were an untouchable and when sunlight falls on him and his shadow falls on a person of the upper caste he or she would feel that he or she has been defiled by the shadow of an untouchable. Similarly, since he is a tree and not an untouchable, the friendship between the cool breeze and the leaves of the tree would be sweet. On the contrary, if he were an untouchable there would be no such sweet friendship. Thus, the speaker wants to argue that the elements of nature enforce equality whereas some sections of human beings enforce inequality. |
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| 11297. |
A wall of 100 metres can be built by 7 men or 10 women in 10 days. How many days will 14 men and 20 women take to build a wall of 600 metres ? (a) 15 (b) 20 (c) 25 (d) 30 |
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Answer» (a) 15 According to question, 10 women = 7 men \(\therefore\) 20 women = 14 men 14 men + 20 women = 14 men + 14 men = 28 men. A wall of 100 m is built by 7 men in 10 days A wall of 100 m is built by 1 man in (10 × 7) days A wall of 1 m is built by 1 man in \(\frac{10\times7}{100}\)days (less length, less days) A wall of 600 m is built by 1 man in \(\frac{10\times7\times600}{100}\) days (more length,more days) A wall of 600 m is built by 28 men in \(\frac{10\times7\times600}{100\times28}\) days = 15 days. |
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| 11298. |
What wouldn’t feel defiled when sunlight embraces the tree in ‘If I was a Tree’? |
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Answer» In the poem, ‘If I was a Tree’, the shadow of the tree would not feel defiled when sunlight embraces it. |
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| 11299. |
When does the poet feel that his shadow wouldn’t be defiled? |
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Answer» If he were to be a tree. |
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| 11300. |
A contractor undertakes to complete a road 360 m long in 120 days and employs 30 men for the work. After 60 days he finds that only 120 m length of the road has been made. How many more men should he employ so that the work may be completed in time ? (a) 20 (b) 30 (c) 15 (d) 45 |
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Answer» (b) 30 Let the number of extra men employed be x. 30 men in 60 days complete 120 m long road. 1 man in 1 day will complete \(\frac{120}{30\times60}\)m long road. Also, (30 + x) men in 60 days complete 240 m long road. \(\therefore\) 1 man in 1 day will complete \(\frac{240}{(30+X)\times60}\)m long road. \(\Rightarrow\) \(\frac{120}{30\times60}\) = \(\frac{240}{(30+X)\times60}\)m \(\Rightarrow\) \(\frac{1}{15}\) = \(\frac{4}{(30+X)}\) \(\Rightarrow\) 30 + x = 60 \(\Rightarrow\) x = 30 \(\therefore\) 30 more men have to be employed |
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