Quantitative Aptitude - Arithmetic Ability Questions

If [a + (1/a)]2 – 2[a – (1/a)] = 12, then which of the following is a value of 'a'?

The list price of an article is Rs. 900. It is available at two successive discounts of 20% and 10% . The selling price of the article is:

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

What number should be added to each of 4, 16, 18 and 58 so that the resulting numbers will be in proportion in the given order?

If the selling price is Rs 1680 after getting a discount of 16%, what was the marked price?

If 2(5x - ­4) -­ 2 < 2x ­- 1 < 4x - ­2; then the value of x is

If a+1a2 = 3, then the value of  a3+1a3 is

If sinA + sin2A =1 then what is the value of cos2A + cos4A