Quantitative Aptitude - Arithmetic Ability Questions

If the amount received at the end of 2nd and 3rd year at compound Interest on a certain Principal is Rs 9,600 and Rs 10,272 respectively, what is the rate of interest (in %)?

Find two numbers such that their mean proportion is 12 and third proportion is 768.

What is the third proportional to 10 and 20?

If 5/2 - (6/5)(x - 15/2) = -x/5, then what is the value of x?

If x – 4y = 0 and x + 2y = 24, then what is the value of (2x + 3y)/(2x – 3y)?

A ladder 20 m long is leaning against a vertical wall. It makes an angle of 30 deg with the ground. How high on the wall does the ladder reach?

If a + b = 8 and ab =15, then a3 + b3 is

A tetrahedron has 4 vertices. How many edges does it have?