Quantitative Aptitude - Arithmetic Ability Questions

If ABCD is a Cyclic Quadrilateral, then the value of Cos2A - Cos2B - Cos2C + Cos2D is

A man has some hens and some cows. If the total number of heads of hens and cows together is 50 and the nunber of feet of hens and cows together is 142, then the number of cows is

What is the difference (in Rs) between compound interest (compounded annually) and simple interest for 3 years on a principal of Rs 4000 at the rate of 30% per annum?

The cash difference between the selling price of an article at a profit of 2% and 16% is Rs.3. The ratio of two selling prices is

'P' is the smallest positive integer such that every positive integer N greater than 'P' can be written as a sum of two composite numbers. Then 'P' is

Find the smallest of the following decimals.

What will come in the place of the question mark (?) in the following number series?305, 338, 404, 503, 635 , (?)

What is the obtuse angle formed by the hands of a clock when the time in the clock is 2:30?