Quantitative Aptitude - Arithmetic Ability Questions

10 identical solid spherical balls of radius 3 cm are melted to form a single sphere. In this process 20% of solid is wasted. What is the radius (in cm) of the bigger sphere?

Diameter of a car wheel is 21 cm. A car driver moving at the speed of 66 km/hr takes 36 seconds to reach a destination. How many revolutions will the wheel make during the journey?

A and B together do a job in 15 days and A alone could do the same job in 20 days. How many days would B take to do half the job if he worked alone?

Two trains, one 150 m long and the other 130m long, coming from opposite directions crosssed each other in 7.2 seconds. The sum of speed of the two trains every hour would then be

If the amount received at the end of 2nd and 3rd year at compound Interest on a certain Principal is Rs 9,600 and Rs 10,272 respectively, what is the rate of interest (in %)?

Select the odd word/letters/number/number pair from the given alternatives.

An article was sold for Rs. 2,400 at a discount of 20%. Find the selling price, if the discount was 25%.

If tan2A - tan2B = x, then the value of x is