Quantitative Aptitude - Arithmetic Ability Questions

If a -­ b = 3 and ab =28, then a3 - b3 is

The difference between cost price and selling price is Rs 494. If loss percentage is 19%, then what is the selling price (in Rs)?

The simple and compound interest that can be earned in two years at the same rate is Rs 4000 and Rs 4180 respectively. What is the rate (percent per annum) of interest?

Two buses are moving towards each other with speed of 20 km/hr and 34 km/hr respectively. What will be the distance (in metres) between the two buses one second before they collide?

Robin can do a work in 10 hours. Pradeep and Robin together can do the same work in 4 hours. Pradeep and Nitin together can do the samework in 5 hours. In how many hours Nitin alone can complete the same work?

A can do a piece of work in 20 days and B in 15 days. With help of C, they finish the work in 5 days. C can alone do the work in

To travel 660 km, an Express train takes 10 hours more than Rajdhani. If however, the speed of the Express train is doubled, it takes 7 hours less than Rajdhani. The speed of Rajdhani is

If sec -5π/4 = x, then the value of x is