Quantitative Aptitude - Arithmetic Ability Questions

The third proportional of two numbers 4 and 20 is

What is the compound interest earned on Rs 80,000 at 40% per annum in 1 year compounded quarterly?

What approximate value should come in place of the question mark (?) in the following questions? (You are not expected to calculate the exact value.)

21.003 × 39.998 –209.91 = 126× ?

If x + y = 13 and x2 + y2 = 89, then find xy is

If (5/9 of x) ­- (2/5 of 9/4) equals ­ -4/5 then find x.

If 4x - 7y = 3 and 2x - y = 9, then x - y is.

At what rate of compound interest (in %) per annum will a sum of Rs. 15,000 become Rs. 18,150 in 2 years?

Choose the odd word/letters/number/number pair from the given alternatives.