Quantitative Aptitude - Arithmetic Ability Questions

If the cost price of 20 books is the same as selling price of 25 books, then the loss percentage is

An angle is smaller than its supplementary by 30°. What is the measure of the angle?

'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 average of all prime numbers from 1 to 50.

If the diameter of the two circles is 6 units and 10 units and a centre distance of 8 units. Calculate the number of common tangents that can be drawn to both the circle.

The 4th and 7th term of an arithmetic progression are 11 and -4 respectively. What is the 15th term?

The sum of three consecutive even integers is 84. Which is the least integer among them?

The 3rd and 6th term of an arithmetic progression are 19 and 37 respectively. What is the 13th term?