What is the greatest possible length of a scale that can be used to measure exactly the lengths 3 m, 5m , 10 m and 12 m 90m,

A. 30 cm

B. 20 cm

C. 10 cm

D. None of these

The average of 7 consecutive numbers is 20. the largest of these numbers is.

A. 22

B. 23

C. 24

D. None of these

In a class of 52 students, the number of boys two less than the number of girls. Average weight of the boys is 42 kg, while the average weight of all students is 40 kg. approximately what is the average weight of girls.

38.14 kg

B. 40 kg

C. 42 kg

D. None of these

If the arithmetic mean of 6 numbers is 45, what is the total sum of these numbers.

A. 27

B. 45

C. 65

D. None of these

The mean of 100 items was found to be 30. if at the time of calculation, two items were wrongly taken as 32 and 12 instead of 23 and 11. the correct mean is ——.

A. 29.7

B. 29.8

C. 29.9

D. None of these

In 1 kg mixture of sand and iron, 20% is iron. How much sand should be added so that proportion of iron become 10%.

A. 1 kg

B. 200 gm

C. 500 gm

D. None of these

In an examination, 65% of the total examinees passed. If the number of failure is 420, the total number of examinees is.

A. 500

B. 1000

C. 1200

D. None of these

How is ½% expressed as a decimal fraction?

A. 0.005

B. 0.05

C. 0.5

D. None of these

The ratio of A’s and B’s salary is 9:4. if A’s salary is increased by 15%, than his total salary becomes Rs5175. what is the salary of B?

A. 2000

B. 4000

C. 4500

D. None of these

The mean proportional of 0.25 and 0.04 is—-.

A. 0.01

B. 0.1

C. 1

D. None of these