Quantitative Aptitude - Arithmetic Ability Questions

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

Value of (cos 53° - sin 37°) is

12 copies of a book were sold for Rs. 1800 thereby gaining cost price of 3 copies. The cost price of a copy of the book is

The simple interest accrued on a sum of money at the end of four years is 1/5th of its principal. What is the rate of interest per annum?

The marked price of a pencil is 35% more than its cost price. What maximum discount percentage can be offered by the shopkeeper to sell his pencil at no profit or no loss?

What will be the net discount (in %) of two successive discounts of 15% and 35%?

The sum of the ages of father and a son presently is 70 years. After 10 years, the son's age is exactly half that of the father. What are their ages now?

Akash is 3 times as good a workman as Baldev and therefore is able to finish a job in 40 days less than Baldev. Working together, they can finish it in _____.