Quantitative Aptitude - Arithmetic Ability Questions

If cosθ = x2-y2x2+y2, then the value of cotθ is

What will be the value of xy, if x2+y2 = 45 and x-y=5 ?

A sum of money (P) doubles in 10 years. How much would it be in 20 years at the same rate of simple interest?

If x2 + ax + b, when divided by x + 3, leaves a remainder of -1 and x2 + bx + a, when divided by x - 3, leaves a remainder of 39, then a+ b = ?

How much does one need to add to 2/3 to obtain 3/2?

If selling price is Rs. 72 and Gain percentage = 20%, calculate the Cost Price.

The value of -3+3+87+43 is

When [x + (1/x)] = 5, then what is the value of [x – (1/x)]?