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14351.

Which of the following is the largest planet, compared to the size of Earth?A. MarsB. JupiterC. UranusD. Saturn1. B2. A3. C4. D

Answer» Correct Answer - Option 1 : B

The correct answer is Jupiter.

  • Jupiter, the most massive planet in the solar system.
  • It is fifth in distance from the Sun.
  • It takes nearly 12 Earth years to orbit the Sun, and it rotates once about every 10 hours, more than twice as fast as Earth.

 

  • Mars, fourth planet in the solar system in order of distance from the Sun and seventh in size and mass. Mars are also known as a red planet.
  • Uranus is the seventh planet in distance from the Sun and the least massive of the solar system’s four giant, or Jovian planets, which also include Jupiter, Saturn, and Neptune.
  • Saturn, second largest planet of the solar system in mass and size and the sixth nearest planet in distance to the Sun.

​ 

  • Total eight planets orbiting the Sun, in order of increasing distance, are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.
14352.

Which is the hottest planet?A. MercuryB. VenusC. EarthD. Mars1. B2. A3. D4. C

Answer» Correct Answer - Option 1 : B

The correct answer is Venus.

  • Venus is the hottest planet in the solar system.
  • Although Venus is not the planet closest to the sun, its dense atmosphere traps heat due to the greenhouse effect makes it our solar system's hottest planet.
  • Venus is known as the twin sister of earth.
  • Venus is also known as the Morning star or Evening star.
  • Hence, option 1 is correct.

  • There are eight planets in the Solar System.
  • From the closest to farthest from the Sun, they are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.
  • The first four planets are called terrestrial planets.
    • They are mostly made of rock and metal, and they are mostly solid.
  • The last four planets are called gas giants.
    • This is because they are much larger than other planets and are mostly made of gas.
  • The Solar System also contains other things.
    • There are asteroid belts, mostly between Mars and Jupiter.
    • Further out than Neptune, there is the Kuiper belt and the scattered disc.
    • These areas have dwarf planets, including Pluto, Makemake, Haumea, Ceres, and Eris.
    • There are thousands of very small objects in these areas. There are also comets, centaurs, and there is interplanetary dust.
14353.

Why is the rate of breathing in aquatic organisms much faster than in terrestrial organisms?

Answer»

Aquatic organisms like fishes obtain oxygen from water present in dissolved state through their gills. Since the amount of dissolved oxygen is fairly low compared to the amount of oxygen in the air, the rate of breathing in aquatic organisms is much faster than that seen in terrestrial organisms.

14354.

Among the crustose, foliose and fruticose lichens which one is a pioneer species?

Answer»

Crustose lichens

14355.

16. CASE STUDVIt was found in a college survey of Janta College that \( 60 \% \) students stay as Paying Guests (PGs) while the remaining are day scholars. Over the last few years, it was reported that \( 20 \% \) PGs get a distinction while \( 30 \% \) day scholars are able to achieve distinction marks in the year end exams. For a randomly chosen student. what is the probability of:(i) achieving distinction marks?(ii) student being a day scholar given that she achieved distinction marks?

Answer»
i) 1/2
ii)3/10



I hope my answer helps you

14356.

Evaluate \( \int \frac{2 \cos x}{\left(\sin ^{2} x+1\right)\left(\sin ^{2} x+2\right)} d x \)

Answer»

Let I = \(\int\frac{2cosx}{(sin^2x+1)(sin^2x+2)}dx\)

Let sin x = t

⇒ cos x dx = dt

\(\therefore\) I = \(\int\frac{2dt}{(t^2+1)(t^2+2)}\) 

\(=2\int\frac{(t^2+2)-(t^2+1)}{(t^2+1)(t^2+2)}dt\) 

\(=2\int(\frac1{t^2+1}-\frac1{t^2+2})dt\) 

\(=2[\int\frac1{t^2+1}dt-\int\frac1{t^2+2}dt)\) 

\(=2[tan^{-1}t-\frac1{\sqrt2}tan^{-1}\frac t{\sqrt2})+c\)

(\(\because\) \(\int\frac{1}{a^2+x^2}dx=\frac1atan^{-1}\frac xa\))

\(=2tan^{-1}t-\sqrt2tan^{-1}\frac t{\sqrt2}+c\)

\(=2tan^{-1}(sin x)-\sqrt2tan^{-1}(\frac{sin x}{\sqrt2})+c\)

(\(\because\) t = sin x)

14357.

If \( y=1+x+\frac{x^{2}}{2!}+\frac{x^{3}}{3!}+---+\infty \), then \( \frac{d y}{d x} \) is equal to

Answer»

y = 1 + x + \(\frac{x^2}{2!}+\frac{x^3}{3!}+....\infty\)

 = e(\(\because\) ex = 1 + x + \(\frac{x^2}{2!}+\frac{x^3}{3!}+....\))

\(\because\) \(\frac{dy}{dx}=\frac d{dx}e^x=e^x=y\) 

or Alternate method:

y =  1 + x + \(\frac{x^2}{2!}+\frac{x^3}{3!}+\frac{x^4}{4!}....\infty\) 

\(\therefore\) \(\frac{dy}{dx}\) = 1 + \(\frac{2x}{2!}+\frac{3x^2}{3!}+\frac{4x^3}{4!}....\infty\)

 = 1 + x + \(\frac{x^2}{2!}+\frac{x^3}{3!}+...\infty\) 

 = y

14358.

The Komodo dragon …………… follow its prey till it will eventually dies due to its venomous bite.a) must b) will c) could d) may

Answer»

Answer is:

b) will

14359.

The LCM of two prime numbers p and q (p > q) is 221. Find the value of 3p – q. (a) 4(b) 28(c) 38(d) 48

Answer»

Correct answer is: (c) 38

LCM of two prime numbers = product of the numbers 221= 13 x 17.

So p= 17 & q= 13

\(\therefore\) 3p - q= 51-13 =38

14360.

Two fair dice are rolled simultaneously. The probability that 5 will come up at least once is (a) 5/36(b) 11/36(c) 12/36(d) 23/36

Answer»

Correct answer is: (b) 11/36

Outcomes when 5 will come up at least once are-

(1,5), (2,5), (3,5), (4,5), (5,5), (6,5), (5,1), (5,2), (5,3), (5,4) and (5,6)

Probability that 5 will come up at least once = 11/36

14361.

A card is drawn from a well shuffled deck of cards. What is the probability that the card drawn is neither a king nor a queen?(a) 11/13(b) 12/13(c) 11/26(d) 11/52

Answer»

Correct answer is: (a) 11/13

Probability that the card drawn is neither a king nor a queen

= (52-8)/52

= 44/52 = 11/13

14362.

Vinit fixes the marked price of a shoe 28% above its cost price. What should be the approximate percentage of discount allowed to gain 6%?1. 15%2. 16%3. 17%4. 14%5. 19%

Answer» Correct Answer - Option 3 : 17%

Given:

M.P = 28% above C.P

Gain = 6%

Formula Used:

Discount% = (M.P – S.P)/M.P × 100

Calculations:

Let the C.P of the shoes be 100.

∴ M.P = 28% of 100

⇒ 128

S.P = 6% of 100

⇒ 106

∴ Discount% = (M.P – S.P)/M.P × 100

⇒ (128 – 106)/128 × 100

⇒ 17.18 ≈ 17%

The discount allowed to gain 6% is 17%.
14363.

`(sqrt2-sin25^(@)-cos25^(@))/(sin25^(@)-cos25^(@))` is equal toA. `tan 25^(@)`B. `cos20^(@)`C. `-tan10^(@)`D. `sec 10^(@)`

Answer» `(sqrt2-sqrt2((1)/(sqrt2)sin25^(@)+(1)/(sqrt2)cos25^(@)))/(sqrt2(1-cos25^(@)-(1)/(sqrt2)cos25^(@)))=(sqrt2-sqrt2cos(25^(@)-45^(@)))/(sqrt2sin(25^(@)-45^(@)))`
`=(sqrt2(1-cos20^(@)))/(sqrt2sin(-20^(@)))=(2sin^(2)10^(@))/(-2sin10^(@)cos10^(@))=-tan10^(@)`
14364.

In a hostel, 60% of the students read Hindi newspaper, 40% read English newspaper and 20% read both Hindi and English newspapers. A student is selected at random.Then find the probability of following events : (i). The student reads neither Hindi nor English newspaper. (ii). If the student reads Hindi newspaper, then find the probability that he reads English newspaper. (iii). Find the probability that student reads Hindi newspaper given that he reads English newspaper. (iv). The student reads only English newspaper. (v). The student reads only Hindi newspaper

Answer»

(i). Let event H and E denotes that students read Hindi newspaper and English newspaper, respectively. 

Since, given that in a hostel, 60% of the students read Hindi newspaper, 40% read English newspaper and 20% read both Hindi and English newspapers . 

Therefore, n(E) = 40%, n(H)= 60% and n(H ∩ E) = 20%. 

Now, we know that n(H ∪ E) = n(H) + n(E) − n(H ∩ E). 

Therefore, n(H ∪ E) = 40 + 60 − 20 = 80%. 

Therefore, 80% students who reads either Hindi or English newspaper in the hostel . 

Therefore, 20% students in the hostel who reads neither Hindi nor English newspaper . 

Therefore, the probability that student reads neither Hindi nor English newspaper is \(\frac{20}{100}= \frac{2}{10} = \frac{1}{5}.\)

(By changing percentage into the probability form. ) 

(ii). Now, the probability that student reads both newspaper is P(H ∩ E) = \(\frac{20}{100}= \frac{2}{10} = \frac{1}{5}\)

(By changing percentage into the probability form.)

And the probability that student read Hindi newspaper is P(H) = \(\frac{60}{100}\) = \(\frac{6}{10}\) = \(\frac{3}{5}\) .

Therefore, the probability that student reads English newspaper given that he reads Hindi newspaper is P(E|H). 

Now, P(E|H) = \(\frac{P(H∩E)} {P(H)}\) = \(\frac{1/5} {2/5}\) = \(\frac{1}{3}\) . (Conditional probability)

Hence, if the student reads Hindi newspaper, then the probability that he reads English newspaper is \(\frac{1}{3}\).

(iii). The probability that student read English newspaper is P(E) = \(\frac{40}{100} = \frac{4}{10} = \frac{2}{5}.\) 

Therefore, The probability that student reads Hindi newspaper given that he reads English newspaper is P(H|E).

Now, P(H|E) = \(\frac{P(H ∩ E)} {P(E)}\)  = \(\frac{1/5} {2/5}\) = \(\frac{1}{2}.\) (Conditional probability) 

Hence, if the student reads English newspaper, then the probability that he reads Hindi newspaper is \(\frac{1}{3}\)

(iv). The students in the hostel who reads only English newspaper is n(Eonly) = n(E) − n(H ∩ E) = 40 − 20 = 20%. 

Therefore, the probability that student reads only English newspaper is P (Eonly) = \(\frac{20}{100} = \frac{2}{10} = \frac{1}{5}.\) 

(By changing percentage into the probability form.) 

(v). The students in the hostel who reads only Hindi newspaper is n(Honly) = n(H) − n(H ∩ E) = 60 − 20 = 40%. 

Therefore, the probability that student reads only English newspaper is P(Honly) = \(\frac{40}{100} = \frac{4}{10}\) = \(\frac{2}{5}\)

(By changing percentage into the probability form. ) 

Hence, the probability that student reads only Hindi newspaper is \(\frac{2}{5}\) .

14365.

Probabilities of solving a specific problemindependently by A and B are`1/2 a n d1/3`respectively. Ifboth try to solve the problem independently, find the probability that (i)the problem is solved (ii) exactly one of them solves the problem.

Answer» Let `P(A)` is the probability that `A` solves the problem and `P(B)` is the probability that `B` solves the problem.
Here, `P(A) = 1/2 and P(B) = 1/3`
`:. P(barA) = 1-1/2 = 1/2`
`P(barB) = 1-1/3 = 2/3`
(i) Probability when the problem is solved:
In this case either one of them or both of them can solve the problem.
So, required probability,
`=P(A)P(barB)+P(B)P(barA)+P(A)P(B)`
`=1/2*2/3+1/3*1/2+1/2*1/3 = 1/3+1/6+1/6 `
`=2/3.`

(ii) Probability when exactly one of them solve the problem :
In this case, required probability `= P(A)P(barB)+P(B)P(barA)`
`=1/2*2/3+1/3*1/2 = 1/3+1/6`
`=1/2.`
14366.

If A and B are two independent events, then show that the probability of occurrence of at least one of and is given by 1 − P(A′)P(B′).

Answer»

Given that events and are two independent events.

Therefore, P(A ∩ B) = P(A)P(B). ...(1) 

Now, the probability of occurrence of at least one of A and B is P(A ∪ B).

We know that P(A ∪ B) = P(A) + P(B) − P(A ∩ B) = P(A) + P(B) − P(A)P(B)(By equation 1) 

⇒ P(A ∪ B) = P(A) + P(B)[1 − P(A)] = P(A) + P(B)P(A′) ( \(\because\) P(A′) = 1 − P(A)) 

⇒ P(A ∪ B) = 1 − 1 + P(A) + P(B)P(A′) = 1 − [1 − P(A)] + P(B)P(A′) 

⇒ P(A ∪ B) = 1 − P(A ′ ) + P(B)P(A ′ ) = 1 − P(A′)[1 − P(B)] ( \(\because\) P(A ′) = 1 − P(A)) 

⇒ P(A ∪ B) = 1 − P(A ′ )P(B ′ ).

Hence, if A and B are two independent events, then the probability of occurrence of at least one of A and B is given by 1 - P(A′) P(B′ ). 

(Hence prove)

14367.

The big gun that Shreedhar saw made of bronzes. Have you seen anything made of bronze? What?

Answer»

Yes, I have seen idols, medals, cannon and decorative goods made up of bronze.

14368.

For the data,\(\begin{array}{*{20}{c}} {x:}\\ {f\left( x \right):} \end{array}\begin{array}{*{20}{c}} 0\\ 5 \end{array}\begin{array}{*{20}{c}} 1\\ 2 \end{array}\begin{array}{*{20}{c}} 2\\ 1 \end{array}\begin{array}{*{20}{c}} 3\\ 3 \end{array}\begin{array}{*{20}{c}} 4\\ 7 \end{array}\)the value of \(\mathop \smallint \nolimits_0^4 2f\left( x \right)dx\) will be:1. 242. 213. 424. 12

Answer» Correct Answer - Option 4 : 12

Concept:

Trapezoidal rule is given by:

\(\mathop \smallint \limits_{\rm{a}}^{\rm{b}} {\rm{f}}\left( {\rm{x}} \right){\rm{dx}} = \frac{{\rm{h}}}{2}\left[ {{{\rm{y}}_{\rm{o}}} + {{\rm{y}}_{\rm{n}}} + 2\left( {{{\rm{y}}_1} + {{\rm{y}}_2} + {{\rm{y}}_3}{\rm{\;}} \ldots } \right)} \right]\)

\({\rm{Number\;of\;intervals(n)}} = \frac{{{\rm{b}} - {\rm{a}}}}{{\rm{h}}}{\rm{\;}}\)

where b is the upper limit, a is the lower limit, h is the step size.

Calculation:

From question

x

0

1

2

3

4

f(x)

5

2

1

3

7

 

\(I = \mathop \smallint \nolimits_0^4 2.f\left( x \right).dx\)

Let f(x) = 2.f(x)

∴ \(f\left( x \right) = \frac{{f\left( x \right)}}{2}\)

\(I = \mathop \smallint \nolimits_0^4 \frac{{f\left( x \right)}}{2} \cdot dx = \frac{1}{2}\mathop \smallint \nolimits_0^4 f\left( x \right) \cdot dx\)

From the formula:

\(\mathop \smallint \nolimits_0^4 f\left( x \right)dx = \frac{h}{2}\left[ {\left( {{y_0} + {y_4}} \right) + 2\left( {{y_1} + {y_2} + {y_3}} \right)} \right]\;\)

\(= \frac{{1}}{2}\left[ {\left( {5 + 7} \right) + 2\left( {2 + 1 + 3} \right)} \right]\)

∴ \(I = \frac{{24}}{2} = 12\)

14369.

What is the number of words that can be formed from the letters of the word 'DAUGHTER', the vowels remaining always together?1. 7202. 43203. 172804. 21540

Answer» Correct Answer - Option 2 : 4320

Concept:

The letters A, E, I, O, and U are called vowels. The other letters in the alphabet are called consonants.

n ! = n(n - 1)(n - 2)....3.2.1

Calculations:

We know that, the letters A, E, I, O, and U are called vowels. The other letters in the alphabet are called consonants.

In the word 'DAUGHTER', the vowels are ‘a, u, e’ and the consonants are “d, g, h, t, r”

All the vowels should come together, so consider the bundle of vowels as one letter, then the total letters will be 6. [(aue), d, g, h, t, r]

So, no. of ways of arranging these letters = 6! × 3! = 4320

14370.

If x, 2x + 2, 3x + 3 are the first three terms of a geometric progression, then 4th term in the geometric progression is1. -13.52. 13.53. -274. 27

Answer» Correct Answer - Option 1 : -13.5

Concept:

If a, b, c are in GP than \(r = \frac{b}{a} = \frac{c}{b}\)

If first term of GP is a and common ratio is r than nth term of GP is given by arn - 1

Calculation:

Given: x, 2x + 2, 3x + 3 are the first three terms of a geometric progression than

\(\frac{{2x + 2}}{x} = \frac{{3x + 3}}{{2x + 2}}\)

\(\frac{{2x + 2}}{x} = \frac{3}{2}\)

\(4x + 4 = 3x \Rightarrow x = - 4 = a\)

\(r = \frac{c}{b} = \frac{{3x + 3}}{{2x + 2}} = \frac{3}{2}\)

4th term in the geometric progression is T4= arn - 1

\({T_4} = ( - 4){\{ \frac{3}{2}\} ^{4 - 1}} = - 13.5\)

Hence, option A is the correct answer.

14371.

The arithmetic mean of two numbers exceeds their geometric mean by 2 and the geometric mean exceeds their harmonic mean by 1.6. What are the two numbers?1. 16, 42. 81, 93. 256, 164. 625, 25

Answer» Correct Answer - Option 1 : 16, 4

Concept:

Let the two numbers as a and b.

A.M. = \(\rm \dfrac {a+b}{2}\)

G.M. = \(\rm\sqrt{ab}\) 

Relation between AM and GM:

(G.M.)2 = (A.M.)(H.M.)

 

Calculations:

Given, the arithmetic mean of two numbers exceeds their geometric mean by 2 and the geometric mean exceeds their harmonic mean by 1.6.

⇒ A.M. = G.M. + 2         ....(1)

and G.M. = H.M. + 1.6

We know that, (G.M.)2 = (A.M.)(H.M.)

⇒ (G.M.)2 = (G.M. + 2)(G.M. - 1.6)

⇒ (G.M.)2 = (G.M.)2 + 0.4 G.M. - 3.2 

⇒ 0.4 G.M. = 3.2

⇒ G.M. = 8                  ....(2)

From equation (1), we get 

⇒A.M. = 10                  ....(3)

Consider, the two numbers as a and b.

then, G.M. = \(\rm\sqrt{ab}\) and A.M. = \(\rm \dfrac {a+b}{2}\)

From equation (2) and (3), we get

⇒ \(\rm\sqrt{ab}\) = 8 and \(\rm \dfrac {a+b}{2}\) = 10

⇒ ab = 64 and a + b = 20 

⇒ a (20 - a) = 64

⇒ a - 20a - 64 = 0

⇒ a =16 or a = 4

⇒ b = 4 or b = 16

Hence, the two numbers are 16 and 4.

Hence, The arithmetic mean of two numbers exceeds their geometric mean by 2 and the geometric mean exceeds their harmonic mean by 1.6. the two numbers are 16 and 4.

14372.

Q) The first , second and middle term of an AP are a,b,c respectively. Sum of all terms is       A) 2(c-a)/b-a.               B)( 2c(c-a)/b-a. ) +c      C) 2c(b-a)/c-a.               D) 2b(c-a)/b-a

Answer» B)

Let's Think , The Common Difference of this AP Series = d

Now , first term = a

           second term = b

So , b = a + d

  Or ,     d = b-a

Now , if there are total ( 2n +1 ) th term in the series , the middle term will be ( n+1) term .

Therefore , c = a + nd = a + n(b-a)

        From this we can get , n = (c-a) / (b-a)

So , the total sum = [(2n+1)/2][2a + 2nd ]

                                = [2*{(c-a)/(b-a)}+1]c

You can find out the last term by putting the value of n and d in the above term and rearranging that .
14373.

If \(\sum_{n=1}^{\infty}\cot ^{-1}(\frac{n^2}{8})\)=\(\frac{a}{b}\pi\) where a/b is a rational number in its lowest form, then correct options is/area) a-b=3b) a+b=11c)a+b=10d) a-b=4

Answer»

Answer: a) a-b=3

14374.

If \( S_{n}=\frac{3 \times 1^{3}}{1^{2}}+\frac{5 \times\left(1^{3}+2^{3}\right)}{1^{2}+2^{2}}+\frac{7 \times\left(1^{3}+2^{3}+3^{3}\right)}{1^{2}+2^{2}+3^{2}}+ \) Which of the following is correct?

Answer»

Sn = \(\frac{3\times1^3}{1^2}+\frac{5\times(2^3+2^3)}{1^2+2^2}+\frac{7\times(1^3+2^3+3^3)}{1^2+2^2+3^2}\) + .... + \(\frac{2n+1)(1^3+2^3+3^3+....+n^3)}{1^2+2^2+3^2+....+n^2}\)

∴ ΣTn = \(\cfrac{(2n+1)\frac{n^2(n+1)^2}4}{\frac{n(n+1)(2n+1)}6}\) 

\(=\frac32 n(n+1)\) 

\(=\frac32(n^2+n)\)

∴ Sn = ΣTn = \(\frac32\)(Σn2 + Σn)

 = \(\frac32(\frac{n(n+1)(2n+1)}6+\frac{n(n+1)}2)\) 

 = \(\frac34\)n(n + 1)\((\frac{2n+1}3+1)\) 

 = \(\frac14\)n(n + 1) (2n + 4)

 = \(\frac12\)n (n + 1) (n + 2)

14375.

The value of \(\cfrac{(1^4+\frac14)(3^4+\frac14)...((2n-1)^4+\frac14)}{(2^4+\frac14)(4^4+\frac14)....((2n)^4+\frac14)}\) is equal to

Answer»

Let P(n) = \(\cfrac{(1^4+\frac14)(3^4+\frac14)...((2n-1)^4+\frac14)}{(2^4+\frac14)(4^4+\frac14)....((2n)^4+\frac14)}\)

Put n = 1, we get P(1) = \(\cfrac{1^4+\frac14}{2^4+\frac14}=\frac{1+\frac14}{16+\frac14}\) = \(\cfrac{\frac54}{\frac{65}4}\)

\(\frac5{65}=\frac1{13}\)

From option (a), \(\frac{1}{4n^2+2n+1}\) at n = 1 = \(\frac1{4+2+1}=\frac17\)

Hence, (a) is wrong.

From option (b), \(\frac1{8n^2+4n+1}\) at n = 1 = \(\frac1{8 + 4 + 1}=\frac1{13}\)

Hence, option(b) may be true.

From option (c), \(\frac1{4(2n^2+n+1)}\) at n = 1 = \(\frac1{4(2+1+1)}=\frac1{16}\)

Hence, option (c) is wrong.

From option (d), \(\frac1{4(8n^2-4n+1)}\) at n = 1 = \(\frac{1}{8-4+1}=\frac15\)

Hence, option(d) is wrong.

Only option (b) may be true.

\(\therefore\) P(n) = \(\frac1{8n^2+4n+1}\) which can be proved by mathematical induction.

14376.

Find the nth term and sum up to 13terms of the sequence: 3,−1, 1/3, -1/9...

Answer»

Given sequence is :

3,-1,\(\frac{1}{3}\),\(\frac{-1}{9}\),....

∴ a1 = 3, a2 = -1, a3\(\frac{1}{3}\), a4\(\frac{-1}{9}\),....

Common ration = r = \(\frac{a_4}{a_3}\) = \(\frac{a_3}{a_2}\) = \(\frac{a_2}{a_1}\) = \(\frac{-1}{3}\) < 1

nth term of given sequence is,

an = arn-1

= 3 x (\(\frac{1}{3}\))n-1

= (-1)n-1 x 3 x \(\frac{1}{3^{n-1}}\)

\(\frac{(-1)^{n-1}}{3^{n-2}}\)

Sum upto 13 terms = S13\(\frac{a(1-r^{13})}{1-r}\)

\(\frac{3(1-(\frac{-1}{3})^{13})}{1-(\frac{-1}{3})}\)

\(\frac{3(1+\frac{1}{3^{13}})}{1+\frac{1}{3}}\)

\(\frac{3(1+\frac{1}{3^{13}})}{\frac{4}{3}}\)

\(\frac{9}{4}\)(1 + \(\frac{1}{3^{13}}\))

14377.

A sequence is obtained by deleting all perfect squares from the set of all natural numbers starting from 1, then

Answer»

Correct option is (C) The reminder is 1 when 931th term is divided by 2

Given sequence is

2,3,5,7,8,10,11,12,13,14,15,17,18,19,20,21,22,23,24,26......

2003rd term = ?

1892th term = 1937

1980th term = 2026

2003rd term = 2026 + (2003 - 1980)

 = 2026 + 23 = 2049

870th term = 901

930th term = 962

\(\therefore\) 931st term = 963

(a, b) \(\frac{T_{2003}}{2048}=\frac{2049}{2048}\) the reminder left 1

option (a), and (b) are false

(c, d) \(\frac{T_{931}}2=481+\frac12\)

Thus, reminder left 1

option (c) is correct

14378.

In how many ways a committee of 4 members can be made out of 5 boys and 4 girls containing at least 2 girls?1. 312. 413. 814. 515. 61

Answer» Correct Answer - Option 3 : 81

Given

Number of boys = 5

Number of girls= 4

Concept

 nCn = nC0 = 1

Calculation

As there is at least 2 girls from the committee of 4 members. Therefore there could be 2,3 and 4 girls in a committee.

So,

5B×  4G 4+ 5B1×  4G 3+ 5 B 2 × 4 G 2

⇒ 1 + (5 × 4!/1! × 4!) × (4 × 3!/3! × 1!) + (5 × 4 × 3!/2 × 1 × 3!) × (4 × 3 × 2 × 1)/(2 × 1 × 2 × 1)

⇒ 1 + 20 + 60

⇒ 81

14379.

The remainder when 75 × 73 × 78 × 76 is divided by 34 is:1. 182. 153. 124. 22

Answer» Correct Answer - Option 3 : 12

Given:

The number is 75 × 73 × 78 × 76.

Concept used:

Divide each number individually by 34 and break it into a small number and find a number smaller than 34.

Calculation:

75 × 73 × 78 × 76 is divided by 34.

⇒ (75 × 73 × 78 × 76)/34

⇒ (75/34) × (73/34) × (78/34) × (76/34)

⇒ 7 × 5 × 10 × 8

⇒ (35 × 80)/34

⇒ (35/34) × (80/34)

⇒ 1 × 12

⇒ 12

∴ The remainder is 12.

14380.

She would like ___ to go in for sport. A) us B) we C) our D) ours E) she

Answer»

Correct option is A) us

14381.

We came out of the swimming pool and dried ________ carefully. A) us B) our C) ourselvesD) ours

Answer»

Correct option is C) ourselves

14382.

Whose is this house? It’s ________ . A) our B) ours C) our one D) ours one

Answer»

Correct option is B) ours

14383.

The resolution of an encoder with 10 tracks will be nearly (a) 0.15° (b) 0.25° (c) 0.35° (d) 0.45°

Answer»

Correct option is (c) 0.35° 

If the encoder has ‘N’ tracks then the resolution = \(\cfrac{360°}{2^N}\)

In the given data N = 10

So, Resolution = \(\cfrac{360°}{2^{10}}\) = 0.35°

14384.

Have you got any brown socks? No, but I’ve got ________ . A) some blue ones B) some blues C) some blue one D) a blue ones

Answer»

Correct option is A) some blue ones

14385.

Which of the following is the greatest among all?1. 8% discount on marked price ₹4002. 12% discount on marked price ₹2403. 7% discount on marked price ₹5004. 10% discount on marked price ₹320

Answer» Correct Answer - Option 3 : 7% discount on marked price ₹500

Given:

As different Discount percentage is given as shown in the question

Formula used:

Discount = Discount% × Marked Price

Calculation:

8% discount on marked price ₹400 = (400 × 8)/100 = ₹ 32

⇒12% discount on marked price ₹240 = (240 × 12)/100 = ₹ 28.8

⇒7% discount on marked price ₹500 = (500× 7)/100 = ₹ 35

⇒10% discount on marked price ₹320 = (320× 10)/100 = ₹ 32

₹ 35

14386.

A publisher gives his distributor a discount of 30% on the printed price of the books. The distributor sells these books to a bookseller at 20% discount on the printed price and the bookseller sells these books at the marked price. Calculate the profit percentage made by the distributor1. \(13 \frac{2}{7}\)%2. \(15 \frac{2}{7}\)%3. \(14 \frac{2}{7}\)%4. \(12 \frac{2}{7}\)%

Answer» Correct Answer - Option 3 : \(14 \frac{2}{7}\)%

Given- 

Discount given by publisher = 30%

Discount given by distributor = 20%

Formula Used-

Selling Price = Marked Price(1 - Discount%)

Profit% = (SP - CP)/CP × 100

Calculation-

Let the printed price of the book be 100

The publisher sells the book to distributor at 100(1 - 30%)

⇒ 70

Distributor sells the book to bookseller at 100(1 - 20%)

⇒ 80

∴ Profit% of distributor = (80 - 70)/70 × 100

⇒ \(14 \frac{2}{7}\)%

14387.

A girl buys 4 chocolate for Rs. 3 and sells them at 5 chocolates for Rs. 4. How much percentage loss or gain does she make?1. Gain \(6 \frac{2}{3}\)% 2. Loss \(6 \frac{2}{3}\)%3. Loss 2%4. Gain 2%

Answer» Correct Answer - Option 1 : Gain \(6 \frac{2}{3}\)

Given:

A girl buys chocolates at 4 for Rs. 3 and sells them at 5 for Rs. 4.

Concept:

This problem can be easily solved by equating number of chocolates.

Calculations:

So, cost price of 20 chocolate = Rs. 15

And, the selling price of 20 chocolate = Rs. 16

Then, profit = Rs. (16) - (15) = Rs. 1

∴ The profit percentage = [(1)/(15) × 100]% = 6(2/3)%.
14388.

A person has to procure an object through series of 9 agents. He agrees to pay 2% of the item cost as commission to first agent. For second agent he agrees to pay 5% more commission than he paid to first, for third agent 5% more than the second and so on. What is the total percentage of commission he paid? (Use 1.095 ≈ 1.55)1. 202. 223. 334. 27.55. 25

Answer» Correct Answer - Option 2 : 22

Let the cost of the object be Rs x

Commission paid to first agent = 2/100 × x = 0.02x

Commission paid to second agent = (100 + 5) /100 × 0.02x = 1.05 × 0.02x

Commission paid to third agent = (100 + 5) /100 × 1.05 × 0.02x = 1.052 × 0.02x …

Commission paid to ninth agent = 1.058 × 0.02x

Total commission paid = 0.02x + 1.05 × 0.02x + 1.052 × 0.02x + … + 1.058 × 0.02x

⇒ 0.02x × (1 + 1.05 + 1.052 + … + 1.058)

⇒ 0.02x × (1.059 – 1) / (1.05 – 1) [∵ Sum of n terms of G.P. = a (rn – 1) / (r – 1)]

⇒ 0.02x × (1.55 – 1) / 0.05 = 0.22x

∴ Commission paid = 0.22x/x × 100 = 22%
14389.

A person working in sales department draws Rs. y as basic salary. Further he gets 10% as commission for every penny more than 1 lakh brought in as sales. He also gets 20% as bonus for every penny more than 2 lakhs he brought in as sales. For a particular sales amount, he receives Rs. 50000 as total salary whereas he would have received only Rs. 15000 for half the sale amount. What is the value of y?1. 100002. 150003. 180004. 200005. 24000

Answer» Correct Answer - Option 1 : 10000

Let the sales he made be Rs. x

If sales are less than 1 lakh, he would have received only basic pay which should be same for half the sales.

∴ Sales > 1 lakh

Let us assume 200000 > x > 100000

Half the sales will be less than 100000

∴ Salary received them = Basic pay = Rs. 15000

Salary received for sale of Rs. x = Basic pay + Commission of 10%

⇒ 50000 = 15000 + (x – 100000) × 10/100 [∵ Commission is paid on every penny above 1 lakh]

⇒ x = 450000

It contradicts the assumption

Let us assume x > 200000

Salary received = Basic pay + Commission of 10% + Bonus of 20%

⇒ 50000 = y + (x – 100000) × 10/100 + (x – 200000) × 20/100

100000 = y + 0.3x      ---- 1

Maximum value of x = 100000/0.3 = Rs. 33333 1/3

∴ Half of sales is always less than Rs. 200000

∴ No bonus is paid when sales is halved

⇒ 15000 = y + 10/100 × (x/2 – 100000)

⇒ 25000 = y + 0.05x   ---- 2

Equation 1 – Equation 2

⇒ 75000 = 0.25x

⇒ x = 300000

Substituting in equation 1

⇒ y = Rs. 10000

∴ The value of y is Rs. 10000.
14390.

A sells a watch to B at a profit of 20% and B sells it to C at a loss of 10%. If C pays Rs. 432, how much did A pay for it?1. Rs. 5002. Rs. 4003. Rs. 2004. Rs. 300

Answer» Correct Answer - Option 2 : Rs. 400

Given-

A sells a watch to B at a profit of 20%

B sells it to C at a loss of 10%

Formula Used-

Profit% = (CP - SP)/CP × 100       [where CP = Cost Price and SP = Selling Price]

Loss% = (SP - CP)/CP × 100      [where CP = Cost Price and SP = Selling Price]

Calculation-

Let the price at which A buys the watch is 100x.

A sells the watch to B at 100x(1 + 20%)

⇒ 120x

B sells the watch to C at 120x(1 - 10%)

⇒ 108x

According to Question -

108x = 432

⇒ x = 4

⇒ 100x = 400

∴ A paid Rs. 400 for the watch.

14391.

A company pays its employee Rs. 10000 as basic salary and 10% of every penny more than Rs. 150000 he brings in as sales. For past four months he had sales of Rs. 250000, Rs. 300000, Rs. 450000 and Rs. 500000 respectively. Had the basic pay been Rs. 12000, 16% commission and the amount of sales was constant for four months, what is the value of the sales for which he would have obtained same sum as salary? (in rupees)1. 2871252. 2781253. 2271854. 2718255. 275182

Answer» Correct Answer - Option 2 : 278125

In original case:

Salary for first month = 10000 + 10/100 × (250000 – 150000) = Rs 20000

Salary for 2nd month = 10000 + 10/100 × (300000 – 150000) = Rs 25000

Salary for 3rd month = 10000 + 10/100 × (450000 – 150000) = Rs 40000

Salary for 4th month = 10000 + 10/100 × (500000 – 150000) = Rs 45000

Total salary = 130000

In changed case

Salary received as basic pay = 4 × 12000 = Rs 48000

Salary received as commission = 130000 – 48000 = Rs 82000

Commission per month = 82000/4 = Rs 20500

Commission = (Sales – 150000) × 16/100

20500 = (Sales – 150000) × 0.16

128125 = Sales – 150000

∴ Sales = 278125
14392.

A company pays its employees Rs. 20000 as basic pay, 10% of every penny more than Rs. 100000 they bring in as sales as commission and 20% of every penny more than Rs. 300000 sales as bonus. An employee working there brought in sales of Rs. 250000, Rs. 500000, Rs. 100000 and Rs. 70000 for four months. If he brought 20% more sales every month, what will be the percentage increase in the total salary?1. 152. 163. 184. 205. 21

Answer» Correct Answer - Option 4 : 20

Salary received as basic pay = 4 × 20000 = Rs. 80000

For month - I

Salary received as commission in original case = 10/100 × (250000 – 100000) = Rs 15000

Salary received as bonus in original case = 0

Total salary except basic = Rs. 15000

When 20% more sales, Sales = 120/100 × 250000 = 300000

Salary received as commission = 10/100 × (300000 – 100000) = 20000

Salary received as bonus = 0

Total salary except basic = Rs. 20000

For month - II

Salary received as commission in original case = 10/100 × (500000 – 100000) = Rs. 40000

Salary received as bonus in original case = 20/100 × (500000 – 300000) = Rs. 40000

Total salary except basic = Rs. 80000

When 20% more sales, Sales = 120/100 × 500000 = 600000

Salary received as commission = 10/100 × (600000 – 100000) = 50000

Salary received as bonus = 20/100 × (600000 – 300000) = Rs. 60000

Total salary except basic = Rs. 110000

For month - III

Salary received as commission in original case = 0

Salary received as bonus in original case = 0

Total salary except basic = Rs. 0

When 20% more sales, Sales = 120/100 × 100000 = 120000

Salary received as commission = 10/100 × (120000 – 100000) = 2000

Salary received as bonus = 0

Total salary except basic = Rs. 2000

For month - IV

Salary received as commission in original case = 0

Salary received as bonus in original case = 0

Total salary except basic = Rs. 0

When 20% more sales, Sales = 120/100 × 70000 = 84000

Salary received as commission in original case = 0

Salary received as bonus in original case = 0

Total salary except basic = Rs. 0

Total salary originally = Rs. 80000 + Rs. 15000 + Rs. 80000 = Rs. 175000

Total salary if 20% more sales = Rs. 80000 + Rs. 20000 + Rs. 110000 = Rs. 210000

% increase in salary = (210000 – 175000) /175000 × 100

⇒ 20%
14393.

In a spring block system on a horizontal smooth surface. K = spring constant, A = amplitude, m = mass of the block. In column I some changes are given and column II respective effect is written. Then select the correct answer using the codes given below the columns. : `{:("Column-I",,"Column-II"),("(P) if mass of the block is doubled (keeping K,A unchanged)",,(1) "time period increases"),("(Q) if the amplitude of oscillation is doubled (keeping m,A unchanged)",,(2)"time period decreases"),("(R) If force constant is doubled (keeping m, A unchanged )",,(3) "energy of oscillation increases"),("(S) if another spring of same force constant is attached parallel to the previous one (keeping m, A unchanged)",,(4) "energy of oscillation remains constant"):}`A. `{:(,P,Q,R,S),((A),1,3,2,3):}`B. `{:(,P,Q,R,S),((B),2,1,3,4):}`C. `{:(,P,Q,R,S),((C),3,4,1,2):}`D. `{:(,P,Q,R,S),((D),4,2,3,1):}`

Answer» `(P) T=2pisqrt(m/k) m uarr T uarr`
`E=1/2 kA^(2)`
`(Q) E=1/2 kA^(2) A uarr Euarr`
`(R) T=2pisqrt(m/k) k uarr T darr`
`E=1/2 kA^(2) kuarr Euarr`
`(S) T=2pisqrt(m/(k_(eq)) k_(eq)) uarr T darr`
`k_(eq) =2k`
`E=1/2 k_(eq) A^(2) k_(eq) uarr Euarr`
14394.

If the transistor in the figure is in saturation than,(a) ic is always equal to βdcib.(b) ic is always to - βdcib.(c) ic is always to βdcidc.(d) ic is less than βdcib.

Answer»

 Correct Option (d) ic is less than βdcib.

Explanation:

For transistor in common emitter mode the relation between collector current and collector emitter voltage is given by vce= vcc-ICRC

cut off

 occurs when Ic= 0 

Saturation

 It occurs when there is no longer a change in collector current for a change in base current

 Active Mode

 In this mode the following relation is valid ic =β Iβ

Thus in saturation the collector current does not increase with base current

14395.

A device used to display one or more digital signals so that they can be compared to expected timing diagrams for the signals is a1. DMM2. Spectrum analyzer3. Logic Analyzer4. Frequency counter

Answer» Correct Answer - Option 3 : Logic Analyzer

A device used to display one or more digital signals so that they can be compared to expected timing diagrams for the signals is a logic analyser.

A spectrum analyzer is an instrument that displays the spectrum of the input waveform with respect to the frequency on the CRT screen.
14396.

An n stage ripple counter can count up to1. 2n2. 2n - 13. n4. 2n-2

Answer» Correct Answer - Option 2 : 2n - 1

An n stage ripple counter can count up to the binary value represented by the n-bits. = 2n - 1

Example:

if n = 3

then count is 0, 1 ,2 ,3 ,4, 5, 6, 7 (order may vary)

that is 2n-1 = 23 - 1 = 7 (maximum value)

14397.

A 5 A, 110 V electrodynamic type wattmeter has a scale having 110 divisions. Its pressure coil is fed by a voltage of [110 √2 cos314) + √2sin(942t) V and its current coil carries a current of [5√ 2cos(314t + 60) + 2√ 2sin (628t + 90) + √2cos(642t + 90)] A. The needle of the wattmeter will move to1. 110 divisions2. 50 divisions3. 54 divisions4. 55 divisions

Answer» Correct Answer - Option 4 : 55 divisions

The average power read by the wattmeter meter, is

\( = { \vee _{rms\;}}{I_{rms}}cos\phi = \frac{{110\;\sqrt 2 }}{{\sqrt 2 }} - \frac{{5\sqrt 2 }}{{\sqrt 2 }}{\rm{cos}}\left( {60°} \right)\)

\(= 110 \times 5 \times \frac{1}{2} = \frac{{550}}{2}\omega \)

Full scale reading of the meter = 110 × 5 = 500 ω

550 ω = 110 divisions

\(\frac{{550}}{2}\omega = \frac{{110}}{2} \Rightarrow 55\;divisions\)

14398.

The superposition theorem is used when the circuit contains A. Reactive elements B. Active elements C. Number of voltage sources D. Single voltage source

Answer»

The superposition theorem is used when the circuit contains number of voltage sources. 

14399.

In a common emitter amplifier, using output resistance of 5000 ohm and input resistance of 2000 ohm, if the input signal voltage is `10mV` and `beta = 50`, calculate output volatge & power gainA. `1.25V, 6250`B. `3V, 6250`C. `1.5V, 3050`D. None of these

Answer» Correct Answer - B
Voltage gain `= beta (R_("out"))/(R_("in"))`
power gain `= beta^(2) (R_("out"))/(R_("in"))`
14400.

What refers to such work at very low temperatures, near absolute zero? A. Cryogenics B. Superconductivity C. Subsonic D. Thermionic

Answer»

Cryogenics refers to such work at very low temperatures, near absolute zero.