Quantitative Aptitude - Arithmetic Ability Questions

The area of the circle with radius Y is W. The difference between the areas of the bigger circle (with radius Y) and that of the smaller circle (with radius X) is W'. So x/y is equal to

2cos[(C+D)/2]sin[(C-D)/2] is equal to

When a discount of Rs. 42 is allowed on the marked price of an article, the new reduced price becomes 86% of the original price. Find the marked price.

If cos3A = X, then value of X?

If a - b = 4 and ab = -3, then what is the value of a3- b3?

For which value of ‘g’ the linear graph of 6x + 12y +9 = 0 and 2x + gy + 3 =0 has infinite number of solutions?

What is the fourth proportional to 24, 120 and 22?

A 145 m long train crosses a 655 m long bridge in 36 seconds. What is the speed of the train?