Quantitative Aptitude - Arithmetic Ability Questions

In ΔDEF measure of angle E is 90°. If cosD = 8/17, and DE = 16cm, then what is the length (in cm) of side DF?

Six year ago Parvez’s age was same as the present age of Manish. If the present age of Parvez is one-fourth more than that of Manish's present age, then in how many years will Parvez’s age become double of Manish’s present age?

Three years ago, the average age of a family of 5 members was 17 years. A baby having been born, the average age of the family is the same today. The present age of the baby is

50 litre mixture of water and alcohol contains 10% alcohol. How much more alcohol must be added to make the strength of alcohol 40% in the new mixture?

The area of a circle is 616 sq.m. Find its diameter.

What is the slope of the line, perpendicular to the line 3x - 6y = 4?

What is the difference (in Rs) in Compound interest earned in 1 year on a sum of Rs 25,000 at 20% per annum compounded semi-annually and annually?

A triangular prism has 9 edges. How many vertices does it have?