The value of $$5-{8+2\sqrt{15} \over4}-{{1}\over8+2\sqrt{15}}$$ is equal to:

If the radius of the base of a right circular cylinder is increased by 20% and the height is decreased by 30%, then what is the percentage increase/decrease in the volume?

Six tables and twelve chairs were bought for ₹ 7,800. If the average price of a table is ₹750, then the average price of a chair would be

Given that x³ + y³ = 72 and xy = 6 with x > y. Then the value of (x – y) is

The compound interest on Rs. 1000 at 10% per annum for 3 years in (Rs.) is

if 2x + 3y = 17 and 2x+2 – 3y+1 = 5, then :

The side of a trapezium pyramid with a square base is 24 cm. and its height is 5 cm. What will be the area of its oblique surface in cm²?

A work could be completed in 100 days by some workers. How- ever, due to the absence of 10 workers, it was completed in 110 days. The original number of workers was: