If the height of a perpendicular cylinder is 10 cm and its curved surface area is 440 square cm, what is its radius?

A contractor undertakes to finish a certain work in 124 days and employed 120 men. After 64 days, he found that he had already done 2/3 of the work. How many men can be discharged so that the work may finish in time ?

In a mixture 25 litres, the ratio of milk and water is 4:1. How many litres of milk must be added to make the ratio 16:1?

The figure below is an equilateral triangle with sides of length 6. What is the area of the triangle?

What should come in place of the question mark '?' in the following number series?

77, 76, 84, 57, ?, – 4

A varies jointly with B and C. A = 6 when B = 3 and C = 2. Find A when B = 5 and C = 7.

What value will come in place of question mark (?) in the questions given below?

837 ÷ ? × 0.8 = 9.3 

What value will come in place of question mark (?) in the questions given below?

663.48 + 22.51 - 292.63 = ? + 300.44