Quantitative Aptitude - Arithmetic Ability Questions

If x = a + 1a, y = a - 1a ,(a>0), then the value of x4+y4-2x2y2 is

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

Consider two-digit numbers which remain the same when the digits interchange their positions. What is the average of such two-digit numbers?

In the following question, select the missing number from the given series.1 108, 81, 54, 27, ?

If 4x2 - 12x + k is a perfect square, then the value of k is

A mixture contains liquid A and liquid B in the ratio of 5 : 4. If 2 litres of liquid B is added to it, then the ratio of liquid A and liquid B becomes 7 : 6. What is the quantity (in litres) of liquid A in the mixture?

On Selling a book at 9/14 of the marked price there is loss of 10%. What will be the ratio of marked price and cost price of the book?

Of the 3 numbers whose average is 40, the first is 1/3 rd the sum of other 2. What is the first number?