A prime number is an integer, or whole number, that has only two factors — 1 and itself. Put another way, a prime number can be divided evenly only by 1 and by itself. Prime numbers also must be ...

How to work out which numbers are multiples of three. A class is asked to find a number from a range between 750 and 800 which is a multiple of three. There is also a demonstration of how to find even ...

The first factor pair is always 1 and the number itself. Consider whether the number is divisible, in turn, by 2, 3, 4, etc. Divide to find the other factor of the pair. All the factors are found when ...