Quantitative Aptitude - Arithmetic Ability Questions

If xy = -30 and x2 + y2 = 61, then find the value of (x + y).

If √(1 - sin2A) = x, then the value of x is

Find the LCM of 3.2, 2.72, 1.28 and 1.44

If a+b=2c then the value of aa-c+cb-c is equal to (where a≠b≠c)

A shopkeeper allows a discount of 20% to his customers and still gains 25%. Find the Marked price of an article which costs Rs.600 to the shopkeeper.

Marked price of an item is Rs 400. On purchase of 1 item discount is 6% and on purchase of 4 items discount is 24%. Rachita buys 5 items, what is the effective discount?

If p/q = (x+3)/(x-3), then what is the value of p2+q2p2-q2 ?

The brother is elder to his sister by 6 years. Seven years ago the product of their ages was 72. What is the age of the brother?