TNPSC GROUP 2 MATHS QUESTIONS WITH ANSWERS

1. The circle graph given here shows the spending of a country on various sports during a particular year. Study the graph and answer the question.

What percentage of the total spending is spent on Tennis?

A. 12.5%

B. 22.5%

C.25%

D.45%

ANS: A

EXPLANATION:

(45/360)×100=12.5%

2. Malini deposited Rs.7000/- with a finance company for 3 years at an interest of 15% per annum. What is the compound interest and the amount that Malini will get after 3 years?

A. C.I – Rs.3246, amount – Rs.13246

B. C.I – Rs.3646, amount – Rs.10646

C. C.I – Rs.6436, amount – Rs.16046

D. C.I – Rs.4636, amount – Rs.14636

ANS: B

EXPLANATION:

Amount= p×(1+r/100)ⁿ

=7000×(1+15/100)³

=7000×(115/100)³

=7000×(23/20)³

=10646

C.I=10646-7000=3646

3. The average salary of all workers in the factory is Rs.60. The average of salary of 12 officers is Rs.400. The average salary of rest is Rs.56. Find the total no of workers in the factory.

A. 1116

B. 1032

C. 1212

D. 1132

ANS: B

EXPLANATION:

12×400+X×56 = (12+X)×60

4800+56X = 720+60X

4X = 4080

X = 1020

Total no of workers = 12+X=12+1020=1032

4. The sides of a triangle are in the ration ½: 1/3: 1/4 and its perimeter is 104 cm. The length of longest side is

A. 52 cm

B. 48 cm

C. 32 cm

D. 26 cm

ANS: B

EXPLANATION:

LCM of 2,3,4 = 12

Therefore ½:1/3:1/4 = 6/12:4/12:3/12 = 6:4:3

6x+4x+3x = 104

13x = 104

x = 8

Longest side = 6x=48

5. If A’s salary is 20% less than B’s salary, by how much percent B’s salary more than A’s?

A. 24%

B. 25%

C. 20%

D. 22%

ANS: B

EXPLANATION:

[20/(100-20)] × 100 =[ 20/80]×100=25%

6. The volume of a cube is 125 cm^3. The surface area of the cube is

A. 625 cm²

B. 125 cm²

C. 150 cm²

D. 100 cm²

ANS: C

EXPLANATION:

a³=125

a=5

Surface area = 6a²=6×25=150cm²

7.  If 50% of (x-y)=30% of (x+y) then what percent of x is y?

A. 25%

B. 50%

C. 75%

D. 100%

ANS: A

EXPLANATION:

50/100 (X-Y) = 30/100 (X+Y)

1/2 (X-Y) = 3/10 (X+Y)

½ X - 3/10 X = 3/10 Y + 1/2 Y

2/10 X = 8/10 Y

Y = ¼ X

¼= 25%

8. 30 percent of a number is 15 less than 3/5^th of a number. What is the number?

A. 48

B. 52

C. 50

D. 70

ANS: C

EXPLANATION:

30/100 X = 3/5 X – 15

 3/10 X – 3/5 X = 15

3/10 X = 15

X = 50

9. The least number which when increased by 1 is divisible by 12,18,24,32 is

A. 278

B. 288

C. 287

D. 279

ANS: C

EXPLANATION:

Required number = [L.C.M of 12, 18, 24, 32] – 1

                        = 288 -1

= 287

10. The missing term in the series 9, 225, 16, 196, 25, 169, ___, 144

A. 81

B. 121

C. 36

D. 49

ANS: C

EXPLANATION:

9, 225, 16, 196, 25, 169, ___, 144

3², 225, 4², 196, 5²,169, 6², 144

6² = 36

10. Find x in 4^x × 64^2x = 16^x+5

A. 1

B. 5

C. 4

D. 2

ANS: D

EXPLANATION:

4^x × (4³)^2x = (4²) ^x+5

4^x × 4^6x = 4^2x+10

4^x+^6x = 4^2x+10

x + 6x = 2x+10

5x = 10

x=2

11. At simple interest Rs. 1000 becomes Rs. 1150 in 3 years. If the interest rate is increased by 3% then the total amount is

A. 1400

B. 1300

C. 1140

D. 1240

ANS: D

EXPLANATION:

S.I = 1150 – 1000 = 150

PNR/100 = 150

(1000×3×R) /100= 150

R = 5

R is increased by 3%, new R = 5+3 = 8%

New S.I = (1000×3×8)/100 = 240

Amount = 1240

12. If 7 spiders make 7 webs in 7 days, then 1 spider will make 1 web in how many days?

A. 1

B. 7/2

C. 7

D. 49

ANS: C

EXPLANATION:

SPIDERS	DAYS	WEBS
7	7	7
7	1	1
1	1	1/7

Therefore it will take 7 days.

13. The following table gives the life time of 500 CFL lamps:

Life time (months)	9	10	11	12	13	14	More than 14	Total
Number of lamps	26	71	82	102	89	77	53	500

A bulb is selected at random. The probability that the life time of the selected bulbatmost 11 months is given by

A. 82/500

B. 179/500

C. 97/500

D. 268/500

ANS: B

EXPLANATION:

(26+71+82)/500 = 179/500

14. Find the missing term in the diagram

4	5		10	8		12	8
20	9		80	18		?	20

A. 25

B. 30

C. 96

D. none of these

ANS: C

EXPLANATION:

4×5 = 20

10×8 = 80

12 × 8 = 96

15. The sum of three prime numbers is 101. The difference of two of them is 24. What are the numbers?

A. 5, 59, 37

B. 41, 53, 7

C. 11, 37, 53

D. 3, 61, 37

ANS: D

EXPLANATION:

Clue: go with options.

3+61+37 = 101

61 – 37 = 24

16. If 18% of the total number of oranges in a basket is 36. Then the total number of oranges is

A. 100

B. 150

C. 200

D. 300

ANS: C

EXPLANATION:

(36/18)×100 = 200

17. The ratio of the prices of two cows was 23:16. Two years later the price of the first cow rises by Rs.477 and that of the second by 10% and the ratio of their pries become 20:11. Find the original prices

A. Rs. 1219, Rs. 848

B. Rs. 1218, Rs. 848

C. Rs. 1210, Rs. 850

D. Rs. 1219, Rs. 840

ANS: A

EXPLANATION:

(23X+477) / [16X + (10/100)] × 16X = 20/11

(23X+477) × 11 = 20 × [16X + (16/10) X]

253X+477×11 = 320X + 32 X

253X+477×11 = 352X

99X = 477×11

X= 477× 11/99

X = 53

23X = 23×53 = 1219

16X = 16×53 = 848

18. A ladder of 25 ft length reaches a window which is 24 ft above the ground level on one side of the street. Keeping its foot at the same point the ladder is turned the other side of the street and now reaches a window of 7 ft high. Then width of the street

A. 30

B. 32

C. 29

D. 31

ANS: D

EXPLANATION: According to Pythagoras theorem a = root of (252- 242)= root of (49)=7 b = root of (252- 72)= root of (576)=24

  

 Width of the street a + b=7+24 = 31

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