InterviewSolution
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.
| 74751. |
15. In a rectangular park of dimensions 50 m x 40 m, a rectangular pis constructed so that the area of grass strip of uniform wsurrounding the pond would be 1184 m. Find the length and breof the pond.Cese |
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Answer» Dimensions = 50 m and 40 mArea of the rectangular lawn= 50× 40 = 2000 m²Area of the grass surrounding the pond = 1184 m²So, the area of the pond = area of the lawn - area of the grass= 2000 - 1184Area of the pond = 816 m²Let the width of around the pond be 'x' mThen, the length of the pond = (50 - 2x) mand the breadth of the pond = (40 - 2x) mArea of the pond = 816 m²⇒ (50 - 2x) ×(40-2x) = 8162000 - 80x - 100x + 4x² = 8164x² - 180x + 2000 - 816 = 04x² - 180x + 1184 = 0dividing it by 4 we getx² -45x + 296 = 0x² - 37x - 8x + 296 =0x(x-37) - 8(x-37) = 0(x-37) (x-8) = 0x= 37 or x = 8supposeif x = 37, thenthe length of the pond will be 50 - 2*3750 - 74 = -24m, which is not possible because length cannot be negative.Therefore the length of the pond = 50 - 2*850 - 16 = 34 mandBreadth of the pond = 40 - 2*840 - 16 = 24 mLength = 34 m and breadth = 24 m |
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| 74752. |
Example 1 Evaluate da1+3sin2xdxSolution: Let21+3sin xDivide numerator and denominator by cos2 x, we getsec2 x dxsecx+3 tan2 x2sec xdx1+4 tan2xLettan x = tsec" xdx = dtdt 1!=f_a_ =-tan-1 (2)=-tan-1 (2 tan x)+c |
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| 74753. |
7.sin 4x sin 8x8. |
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| 74754. |
(x^(a %2B b)/x^(2*c))*((x^(a %2B c)/x^(2*b))*(x^(b %2B c)/x^(2*a))) |
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Answer» 1 is the correct answer of the given question |
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| 74755. |
c ) ^ 2 %2B ( c - a ) ^ 2 %2B ( b - d ) ^ 2 = ( a - d ) ^ 2 |
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Answer» (b-c)^2 + (c-a)^2 + (d-b)^2 = (a-d)^2 Let a = p, b = pr , c = pr² and d = pr³ Now, LHS = (b - c)² + (c - a)² + (d - b)² = (pr - pr²)² + (pr² - p)² + (pr³ - pr)² =( p²r² + p²r⁴ - 2p²r³) + (p²r⁴ + p² - 2p²r²) + (p²r^6 + p²r² -2p²r⁴) = p²r^6 - 2p²r³ + p²= (pr³) -2(pr³)(p) + p²= (pr³ - p)²= (p - pr³)² =(a - d)² = RHS Lke my answer if you find it useful! |
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| 74756. |
12. The mean and median of 100 observations are 50 and 52respectively. The value of the largest observation is 100. Itwas later found that it is 110 not 100. Find the true mean andmedian.24 |
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Answer» Mean = 50.ie∑x / 100 = 50 , where x are the observationstherefore∑x = 50 * 100 = 5000now, 100 is actually 110, so new∑x = 5000 - 100 + 110new∑x = 5010new mean = new∑x/ 100 = 5010/100 = 50.1 new median = 52, as median remains unchanged as it is the middlemost observation, hence 110 has no effect on the median as it is the highest observation |
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| 74757. |
12. The mean and median of 100 observations are 50 and 52respectively. The value of the largest observation is 100. Itwas later found that it is 110 not 100. Find the true mean andmedian.24. |
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| 74758. |
12. The mean and median of 100 observations are 50 and 52respectively. The value of the largest observation is 100. Itwas later found that it is 110 not 100. Find the true mean and 2median. |
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Answer» Solution no. 1:-Arithmetic Mean = ∑X/NGiven : Mean = 50 and N = 100Therefore,50 =∑X/100∑X(Wrong) = 5000Correct value = 110Incorrect value = 100Correct Arithmetic Mean = {∑X (Wrong) + Correct valueof observation- Incorrect value of observation}/N⇒ Correct Mean = (5000 + 110 - 100)/100⇒ Correct mean = 5010/100⇒ Correct Mean = 50.1Answer Solution no. 2 :-In this question, 'the value of thelargest item' should be written instead of 'latest item'.The value of the Median will not change because whatever values are added or subtracted from median, the total observation will remain 100 and median is the centrally located value of a series such that the half of the value or items of the series are above it and the otherhalf arebelow it.Formula of median = Size of(N+1)/2th ItemTotal observations = 100Size of (N+1)/2th item⇒(100+1)/2th Item⇒ 101/2⇒ 50.5th Item110 is corrected observation instead of 100 and 110 is the largest of all the observation. So it will not make any difference in value of median. The value of Median will be 52.Answer |
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| 74759. |
12. The mean and median of 100 observations are 50 and 52respectively. The value of the largest observation is 100. Itwas later found that it is 110 not 100. Find the true mean and24.1 median. |
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| 74760. |
In a boat 25 persons were sitting. Their average weight increaskilogram when one man goes and a new man comes in. The weightman is 70 kgs. Find the weight of the man who is going.1) 50 Kgs 21 45 Kgs 3) 54 Kgs42 Kg |
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Answer» W1 = avg weight initially 25 * W1 = weight of 25 persons in itiallyLet weight of the man who leaves = Wremaining 24 persons weight is = 25 W1 - WWhen new man comes in total weight = 25 W1 - W + 70 Average weight of the new set of 25 persons = (25 W1 - W +70) / 25 = W1 + 1 one more than previous average=> 25W1 - W +70 = 25 W1 + 25=> W = 45 Kganswer |
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| 74761. |
7. The perimeter of a rectangular garden is 160 m. If it is 10 m wide, find its area. |
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Answer» Perimeter=2(l+b)160=2(l+10)80=l+10l=70mArea is l*b=70*10=700m^2 |
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| 74762. |
l. Around a rectangular garden of length 10 m and width 5 m, a road I m wide is laid. Find the cost ofmetallingthe road at 200 per m^2 |
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Answer» ty |
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| 74763. |
ensions of a rectangular plot are 35 m by 20 m. A path of uniform width 2 m isthe border and inside it. Find the cost of paving the path with bricks at t 25 persquare metre and also the cost of covering the remaining part of the plot with gras aalong19 per square metre |
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| 74764. |
In a rectangular park of dimensions 50 m x 40 m, a rectangular pondis constructed so that the area of grass strip of uniform widthsurrounding the pond would be 1184 m^2. Find the length and breadthof the pond. |
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Answer» Dimensions = 50 m and 40 mArea of the rectangular lawn= 50× 40 = 2000 m²Area of the grass surrounding the pond = 1184 m²So, the area of the pond = area of the lawn - area of the grass= 2000 - 1184Area of the pond = 816 m²Let the width of around the pond be 'x' mThen, the length of the pond = (50 - 2x) mand the breadth of the pond = (40 - 2x) mArea of the pond = 816 m²⇒ (50 - 2x) ×(40-2x) = 8162000 - 80x - 100x + 4x² = 8164x² - 180x + 2000 - 816 = 04x² - 180x + 1184 = 0dividing it by 4 we getx² -45x + 296 = 0x² - 37x - 8x + 296 =0x(x-37) - 8(x-37) = 0(x-37) (x-8) = 0x= 37 or x = 8supposeif x = 37, thenthe length of the pond will be 50 - 2*3750 - 74 = -24m, which is not possible because length cannot be negative.Therefore the length of the pond = 50 - 2*850 - 16 = 34 mandBreadth of the pond = 40 - 2*840 - 16 = 24 mLength = 34 m and breadth = 24 m |
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| 74765. |
If sin x + sin²x = 1, thecos^8x+ 2 cos^6x + cos^4x:(1) 0(2) -1(4) I(3) 2 |
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Answer» Sinx +sin²x=1sinx=1-sin²xsinx=cos²xsin²x=cos⁴xso,cos^8x+2cos^6x+cos⁴x=cos⁴x(cos⁴x+2cos²x+1)=sin²x (sin²x+2sinx+1)=sin⁴x+2sin³x+sin²x=sin⁴x+sin³x+sin³x+sin²x=sin²x(sin²x+sinx)+ sinx(sin²x+sinx)=sin²x×(1)+ sinx(1)=sin²x+sinx= 1 |
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| 74766. |
If cos x + cos^2 x = 1, then the value of sin^4x + sine^6x is equal to |
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Answer» Since cosx+cos^2x=1, then cosx=1-cos^2x=sin^2x.Thensin^12x+3sin^10x+3 sin^8x+sin^6x+2 sin^4x+2sin^2x-2= cos^6x+3cos^5x+3 cos^4x+cos^3x+2 cos^2x+2cosx-2=cos^6x+3cos^5x+3 cos^4x+cos^3x=cos^4x (cos^2x+3) + cos^3x(3cos^2+1)= cos^4x (1-cosx+3) +cos^3x(3-3cosx+1)= (1-cosx)^2 (4-cosx)+cosx((1-cosx)(4-3cosx)= (1-2cosx+1-cosx)(4-cosx)+cosx(4-7cosx+3-...= (2-3cosx)(4-cosx)+ cosx(7-10cosx)= 8-14cosx+3cos^2x+7cosx-10cos^2x= 8-7cosx-7cos^2x=8-7(1)= 1 |
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| 74767. |
bought a calculator for eachcalculator cost $14student at the school. Eachare 684 students in the school.money did the principal spend onHo |
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Answer» cost of each calculator is 14 dollartotal cost for 684 students = 14×684= 9576 dollar |
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| 74768. |
7.sin 4x sin 8x |
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| 74769. |
-(a %2B c)^2 %2B (a %2B b)^2 - (b %2B c)^2=0 |
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| 74770. |
bservations is 25. If one observation, namely 25, is deleted, the new mean'isa) 25Median of x.. r. 2 r ยกs 6 and rb) 20c) 28d) 2229,: |
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Answer» New Sum of Observations = 25*10 - 25= 225New Mean = 225/9 = 25. |
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find the products given below and in each case verify the result for a=1,b=2,c=3:(2/5 a2b) x (-15b2ac)x(-1/2c2) |
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| 74772. |
The median of a set of 9 distinct observationsis 20.5. If each of the largest 4 observationsof the set is increase by 2, then the median ofthe new set : |
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Answer» As there are 9 observations arranged in ascending order then median is 5th observation So, 5th observation = 20.5 When largest four observations increased by 2 there will be no change in 5th observation. Therefore, median for new set remain same as of old set which is 20.5 |
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| 74773. |
MathsA lawn is in the shape of a rectangle of length 80 m and width 40 m. Outside the lawn there isfootpath of uniform width 3 cm. Find the area of the path.(A) 756 m(B) 706 m? (C) 736 m² (D) 726 m |
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Answer» c is correct answer for your questions a is the right answer A is the right answer a is the right answer 756m2 is the right answer option a is correct answer. |
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| 74774. |
A rectangular garden 10 m by 16 m is to be surrounded by a concrete walk of uniformwidth. Given that the area of the walk is 120 square metres, assuming the width of thewalk to be x, form an equation in x and solve it to find the value of x. |
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Answer» Length of the rectangular garden = 16 m Breadth of the rectangular garden = 10 m Area of the rectangular garden = 16*10 = 160 m² Area of the concrete path of width x meters (given) = 120 m² Total area = area of rectangular garden + area of the path ⇒ 160 + 120 = 280 m² The width of the concrete path is uniform (Given) So, Length of the whole rectangle (including concrete path) = (16 + 2x) m Breadth of the whole rectangle (including concrete path) = (10 + 2x) m ⇒ (16 + 2x)*(10 + 2x) = 280 ⇒ 4x² + 52x + 160 = 280 ⇒ 4x² + 52x + 160 - 280 = 0 ⇒ 4x² + 52x - 120 = 0 ⇒ Dividing the whole equation by 4, we get. ⇒ x² + 13x - 30 = 0 ⇒ x² + 15x - 2x - 30 = 0 ⇒ x(x + 15) - 2(x + 15) = 0 ⇒ (x - 2) (x + 15) = 0 ⇒ x = 2 or x = - 15 As the width cannot be negative. So, the value of x is 2 x = 2 m Length of the outer rectangle = 16 + (2*2) = 20 mBreadth of the outer rectangle = 10 + (2*2) = 14 m |
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| 74775. |
sin? CosO+tanOsinŠ+ cosâ Q= sech |
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| 74776. |
als22-3sin x+5x)sin x-COSX21-2 sin x cosx2sÄąn x cos x |
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| 74777. |
52. Find the total cost of levelling the shaded path ofuniform width 2 m, laid in the rectangular fieldshown below, if the rate per ma is 100.15 m50 m |
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Answer» total height= 15area along height = lb = 15×2= 30 m^2total length of road = 50area along length= 50×2=100n^2total area of path = 100+30=130 m^2cost = 130×100= 13000₹ height÷15, area height=lb=15×2=30 m^2, area along length=50(2)=100m^2, total area of path=100+30=130m^2, cost =130x100=13000 Rs. |
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show that(ltcote ) C1-Coso) (Itcoso) |
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Answer» (1+ cotx^2)( 1- cosx)( 1+ cosx) = ( cosecx^2)(1- cosx^2) = ( cosecx^2)( sinx^2)= ( sinx^2)( sinx^2)= sinx^4 |
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| 74779. |
Differentiate each of the following w.r.t. x:1. sin 4x2. cos 5x |
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Answer» 1. 4 cos4x. 2.-5 sin5x. (1) 4 cos4x (2) - 5 sin5x |
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The following data shows India's total population (in millions) from 1951 to 2001.1951 | 1961 | 1971 | 1981 I 1991 I 2001360Year of censusPopulation (in millions)432540684852 102Represent the above data by a bar graph. |
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Answer» thanks |
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| 74781. |
( a %2B b %2B c ) ^ 3 - a ^ 3 - b ^ 3 - c ^ 3 = 3 ( a %2B b ) ( b %2B c ) ( c %2B a ) |
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Answer» (a+b+c)3 - a3-b3-c3 = [(a+b)+c]3 – a3-b3-c3 (a+b)3+c3+3c(a+b)(a+b+c)-a3-b3-c3 A3+b3+3ab(a+b)+c3+3c(a+b)(a+b+c)-a3-b3-c3 A3+b3+c3+3ab(a+b)+3c(a+b)(a+b+c)-a3-b3-c3 3ab(a+b)+3c(a+b)(a+b+c) 3(a+b)[ab+c(a+b+c)] 3(a+b)[ab+ac+bc+c2] 3(a+b)[a(b+c)+c(b+c)] 3(a+b)(b+c)(c+a) |
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| 74782. |
Rectangular park and circular park has equal areas of perimeter of rectangle is 58 m and its length is (15 m) more than its breadth, find radius of circle? |
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Answer» I THINK ITS ANSWER IS 115.5cm2 |
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(c)Find the median of the data : 19, 25, 59, 48, 35. 31, 30, 32, and sby 52, what will be the new median ? |
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Answer» Given that,19,25,59,48,35,31,30,32,51. ( put all of the values into order, median is the middle value). 19,25,30,31,32,35,48,51,59. median = 32. if 25 is replaced by 52, ie, 19,30,31,32,35,48,51,52,59. median = 35. |
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LLn the following data, calculate the percentage of workervagesveen Rs. 22 and Rs. 58 :es (in RS): 0-10 10-20 20-30 30-40 40-50 50-60 60-70 70-80 Total204585 160Fuency:70 55 351 30 500C.U. B.Com. 2 |
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| 74785. |
A solid metallic sphere of diameter 8 cm is melted and drawn into acylindrical wire of uniform width. If the length of the wire is 12m,findits width.CBSE 2013] |
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| 74786. |
Illustration 2.39 If A-4sin θ + cos20, then which of thefollowing is not true?a. Maximum value of A is 5b. Minimum value of A is -4.c. Maximum value ofA occurs when sin θ-1/2.d. Minimum value ofA occurs when sin θ:-1 |
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Answer» c and d are incorrect options |
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| 74787. |
p 1: Place the numbers inthe columns correctly |
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Answer» 2572 + 2326 = 4898 |
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| 74788. |
3 A solid metallic sphere of diameter 8 cm is melted and drawn into a cylindrial wmCBSEuniform width. If the length of the wire is 12 m, find its width. |
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| 74789. |
sin 5x -2sin x +sin xProve that= tan x .cos 5x COS X |
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| 74790. |
If f(x)= x + bx? + ax satisfies the conditions on Rolle's theorem on [1.31 with c = 2 +.then(a, b) -(a) (11,6)Cabo(b)(11,-6)(c) (-6, 11)(d) (6, 11) |
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Answer» (b)(11,-6) is correct answer option b is the right answer option b is the right answer option b is the right answer option b is the right answer option b is the right answer the correct answer is B 2 .(11,-6) is the right answer |
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| 74791. |
(a) 3bj-3(c) 6(d)-63. Which of the following is a zero of the polynomial +2-5x-6(a) -2(b) 2(c)-3(d) 3 |
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| 74792. |
15, The diameter of a circular park is 84 m. On its outside, there a 3.5 m wide road.Find the cost of constructing the road at240 per m |
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Answer» 2r=84m (given)r =84/2=42m outer circle's radius=42+3.5=45.5minner circle's radius=42m area of path = (area of outer circle) - (area of inner circle) Radius of the park = 84/2 = 42marea of the park = (22/7)×42×42 = 5544m^2width of road = 3.5m.•.total radius = 3.5+42 = 45.5mtotal area = (22/7)×45.5×45.5 = 6506.5m^2area cover by the road=6506.5-5544= 1062.5m^2total cost of constructing the road=1062.5×240=Rs255000 hit like if you find it useful |
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| 74793. |
at the following tables and point out in which cases do c ard b vary directily?,ok80 1002004091810201530603080 160 |
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| 74794. |
17. Pind the mean of the following data, using the assumed -mean method0-20 20-40 40-60 60-80 80-100 100-120ClassFrequency20 35 52 44383118. The follouing tabl |
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Answer» thanks |
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| 74795. |
6. The length of a tangent from a point A at distance 5 cm from the centre of the circle is 4Vcm. Find the radius of the circle. |
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| 74796. |
LATION BETWEEN RADIUS OF CURVATURERFOCAL LENGTH OF A SPHERICAL MIRRORa spherical mirror of aperture smaller as compared to its radius ofcurature,hirror is one-half the radius of curvature. It is true for concave and converbodhe focal length and 'R' is the radius of curvature of a concave or convermir |
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Answer» The focal length (f) of a lens is the distance between the center of the lens and the point at which the reflected light, of a beam of light travelling parallel to the center line, meets the center line (principal axis). The radius of curvature (r) is the radius of the lens that forms a complete sphere. Looking at the attached diagram we can say the following: The red line represents the light hitting the lens (AB) and reflecting off of the lens (BF). We know that the green line, RB, which represents the radius line of the circle, bisects the angle ABF because it is always at right angles to the lens. Therefore angles ABR and RBF are equal. We also know because of the rule of alternate angles that angle ABR is equal to angle BRF. Therefore, triangle BRF is an isosceles triangle. Consequently the lines BF and RF are equal. We also know that BF and FC are approximately equal for lens that are small. Therefore: RF=BF=FC and RC=RF+FC=FC+FC=2FC or r=2f Therefore, the radius of curvature is twice the focal length. |
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| 74797. |
22. The system of linear equations 5x +my10 and4x + ny 8 have infinitely many solutions, where mand n are positive integers. Then, the minimumpossible value of (m+ n) is equal to(2) 5(4) 10(3) 6 |
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Answer» Then, m+n=? |
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| 74798. |
22. The system of linear equations 5x + my10 and4x + ny 8 have infinitely many solutions, where mand n are positive integers. Then, the minimumpossible value of (m + n) is equal toIS(2) 5(4) 10(3) 6 |
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| 74799. |
Prove that: in 8x cos x in 6xcon 3xeos 2x cos x - sin 3x sin 4x |
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| 74800. |
Q. 15. Prove thatcot 4x(sin 5x + sin 3x) = cot x (sin 5x-sin 3x) |
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