Quantitative Aptitude - Arithmetic Ability Questions

If a + b = 11 and a2+ b2= 61, then value of ab is

5% discount is offered on an item. By applying a promo code the customer wins 20% cash back. What is the effective discount?

The mean of marks secured by 55 students in division A of class X is 58, 45 students of division B is 54 and that of 75 students of division C is 52. Find the mean of marks of the students of three divisions of Class X.

Rithika had Rs 8000. She invested some of it in savings scheme P and the rest of the money in savings scheme Q. She invested for 3 years in savings scheme P and for 2 years in savings scheme Q. savings scheme P offers SI at a rate of 20% pa while savings scheme Q compounded annually at the rate of 30% pa. The interest received from savings scheme P is 930 more than the interest received from savings scheme Q. If Rs 1500 is debited from the invested amount of savings scheme P then find the difference between the amount invested by Rithika in savings scheme P & savings scheme Q.

If x3 – y3 = 81 and x – y = 3, then what is the value of x2 + y2?

A 12 m long wire is cut into two pieces, one of which is bent into a circle and the other into a square enclosing the circle. What is the radius of the circle?

If 3x + [1/(5x)] = 7, then what is the value of 5x/(15x2+ 15x + 1)?

A can do 75% of a job in 18 days and B can do 25% of the job in 12 days. If they work on it together, in how many days can they do 75% of the job?