The ratio of salary of X, Y and Z is 15 : 3 : 8. If Z gets Rs. 3960 more than Y, then what is the salary (in Rs.) of X?

If the side of a square is increased by 20%, then what will be the percentage increase in its perimeter?

For the figure given below, find the value (in degrees) of 2∠A + ∠B.

For the figure given below, find the angle OAB (in degrees).

If XY = a+23 and YX = 13, then find the value of X2 + Y2X2 - Y2.

If 3√7 + √343 = 19.21, then find the value of √252 + 20√7.

Find the least number among  59, 949, 0.43 and 0.72.

Find the average of all prime numbers from 1 to 50.