The smallest number, which when added to 680621 gives the sum a perfect square number, will be

The total number of digits used in numbering the pages of a book of 366 pages 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? 

Find the solution of 5x-7=12? 

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? 

Select the set in which the numbers are related in the same way as the numbers of the following set.
 (12, 30, 204)

Three different containers contain 130 liter, 442 liter and 234 liter of milk, respectively. What biggest measure can be used to measure all the containers exactly?

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