Quantitative Aptitude - Arithmetic Ability Questions

For what sum will the simple interest at R% for 2 years will be R?

The ten's digit of a 2­digit number is greater than the units digit by 4. If we subtract 36 from the number, the new number obtained is a number formed by interchange of the digits. Find the number.

The ratio 1 : 5 can be expressed in decimal as

A number is greater than thrice its reciprocal by 26/3. What is the number?

When a discount of 25% is given on a box of popcorn, the profit is 25%. If the discount is 10%, then the profit is

A thief is stopped by a policeman from a distance of 400 metres. When the policeman starts the chase, the thief also starts running. Assuming the speed of the thief as 5 km/h and that of policeman as 9 km/h, how far the thief would have run, before he is over -taken by the policeman?

A can do a piece of work in 10 days and B can do it in 12 days. They work together for 3 days. Then B leaves and A alone continues. 2 days after that C joins and the work is completed in 2 days more. In how many days can C do it, if he works alone ?

10 people can build a wall in 12 days. Six people, each only half as efficient as those in the first group, will be able to complete 3/5 of such a wall in