Quantitative Aptitude - Arithmetic Ability Questions

ABCD is a quadrilateral in which BD and AC are diagonals then

A shopkeeper marks the price of an article at Rs. 320. Find the cost price if after allowing a discount of 10%, he still gains 20% on the cost price.

Calculate the simple interest if Rs. 1800 is invested for 10 years at a rate of 5% per annum.

Car B is twice as fast as car A. If car A covers 90 km in 2 hours, what is the speed of car B?

P and Q together can make a door in 12 days. They started the work together but after 8 days P left the work. The remaining work is completed by Q alone in 7 more days. In how many days can P alone complete the entire work?

Twenty one times of a positive number is less than its square by 100. The value of the positive number is

The sum of the digits of a 2­digit number is 17. If we add 9 to the number, the new number obtained is a number formed by interchange of the digits. Find the number.

When 0.363636.....is converted into a fraction, then the result is _____.