What is the average of the first 13 odd numbers?

The difference between a number and the square root of the number is 2. The number is:

If the 8 digit number 789x531y is divisible by 72, then the value of (5x - 3y) will be?

Which of the following options has the greatest value?

(49)¹⁵ – 1 is exactly divisible by: 

The digit in unit’s place of the product 81 × 82 × 83 × ... × 89 is

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

In a group of 35 people, 23 of them like coffee, 24 of them like tea and each person likes at least one of the drinks. How many like both?