A prime number has exactly two factors, itself and one. The first ten prime numbers are \({2}\), \({3}\), \({5}\), \({7}\), \({11}\), \({13}\), \({17}\), \({19 ...

A multiple is a number multiplied. So 20, 30 and 40 are multiples of 10. A factor is any number that is evenly divided into another. For example, 2 and 5 are both factors of 10. Exercise that ...