What is the average of the first 13 odd numbers?

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

The sum of the two - digit number is 6 and the number and its flip (digits written in reverse order) both are multiples of 3. If the difference between them is 36, then which of the following is the required number and its flip? 

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

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