If the 4-digit number x 67 y x67y x 67 y is exactly divisible by 9, then what is the least value of ( x + y ) (x + y) ( x + y ) ?

Given n = 1 + x and x is the product of four consecutive integers. Then which of the following is tr...

If x is an even number, then $x^{4n}$, where n is a positive integer, will always have...

If m and n are positive integers, then the digit in the unit's place of $5^n$ + $6^m$ is always...

How many prime numbers are there between 0 and 50?...

What is the sum of all prime numbers between 1 and 20? ...

The sum of three prime numbers is 100. If one of the numbers is 36 more than another, find one of t...