PRACTICE SET - MATHEMATICS

1. Dibya's salary was Rs.18,000. An increase of 20% each in two consecutive years is equal to a single increment of what percentage ?

A. 22%

B. 32%

C. 40%

D. 44%

2. What is the number when multiplied by 16 increases by 540 ?

A. 30

B. 36

C. 42

D. 46

3. The LCM of two prime numbers x anf y is 161. If x ＞ y, then the value of 15y − 7x is :

A. − 32

B. − 56

C. 38

D. 74

4. How many numbers from 1 to 20 are either a multiple of  3 or 5 ?

A. 9

B. 8

C. 689

D. 5

5. Find the unit digit of the expression:

77 ✕ 88 + 66 ✕ 55 = ?

A. 7

B. 6

C. 5

D. 0

6. The sum of the present age of mother and her son is 60 years. Six years ago,  the age of the mother was five times the age of her son. What will be the age of her son after 6 years ?

A. 23 years

B. 22 years

C. 21 years

D. 20 years

7. The incomes of A, B, C are in the ratio 12 : 9 : 7 and their spending are in the ratio 15 : 9 : 8. If A saves 25% of his income,  then what is the ratio of savings of A, B and C ?

A. 11 : 13 : 18

B. 15 : 18 : 11

C. 16 : 17 : 21

D. 13 : 16 : 11

8. If two-third of three-fourth of a number is 34, then what is the value of 20% of that number?

A. 13

B. 13.6

C. 14

D. 14.6

9. Two dice are thrown.  What is the probability that the sum of numbers on the dice is a prime number?

A. 1/6

B. 1/2

C. 1/3

D. 5/12

10. If 20 boys and 20 girls eat 20 apples in 20 minutes,  in how many minutes will one boy and one girl eat one apple?

A. 2 minutes 

B. 1 minutes 

C. 20 minutes 

D. Cannot be determined 

11. A man swims 12 km downstream and 10 km upstream.  If he takes 2 hours each time, then what is the speed of the stream?

A. 1.5 km/hr

B. 1.7 km/hr

C. 0.7 km/hr

D. 0.5 km/hr

12. Half of X, one third of Y and one fifth of Z are all equal.  Find X : Y : Z.

A. 3 : 4 : 5

B. 2 : 3 : 4

C. 1 : 2 : 3

D. 2 : 3 : 5

13. The mean of five numbers is 30. If one number is excluded,  their mean becomes 28. The excluded number is:

A. 26

B. 34

C. 38

D. 46

14. The average cost of 5 jeans and 7 shirts is Rs.600 and the average cost of 5 jeans is Rs.740, then average cost of 7 shirts is :

A. Rs.500

B. Rs.560

C. Rs.450

D. Rs.480

15. If a car moves from A to B at a speed of 60 km/hr and comes back from B to A at a speed of 40km/hr, then its average speed is:

A. 46km/hr

B. 50km/hr

C. 56km/hr

D. 48km/hr

16. Find the sum of odd numbers from 1 to 111?

A. 3136

B. 3223

C. 3256

D. 3526

17. Which among the following is a pair of co-primes?

A. (14, 21)

B. (18, 25)

C. (31, 62)

D. (32, 62)

18. 20 liters of chemical A is added to  80 liters of mixture which is 10% chemical A and 90% chemical B. What percentage of the resulting mixture is chemical A?

A. 18%

B. 15%

C. 28%

D. 40%

19. The ratio between length and breadth of a rectangular jogging park is 3 : 2. If Ashish cycling along the boundary of the park at the speed of 12km/hr completes one round in 8 minutes,  then the area of the park (in sq. m) is :

A. 307200 sq. m

B. 30720 sq. m

C. 153600 sq. m

D. 15360 sq. m

20. Find the number which when multiplied by 17 increases by 208.

A. 14

B. 12

C. 13

D. 15