I’ve probably already used a few words, that you are unfamiliar with. So let’s start with them. Any whole number that can divide exactly into another number, with nothing left over is a Factor. For example, the number six can be divided by two, exactly three times or in other words, two times three equals six. So the numbers two and three, are factors of six. But two isn’t a factor of seven, and neither is three, because if we divide seven by two or three we get one left over. A factor doesn’t leave any remainders. But let’s go back to six. One times six equals to six too. So, the numbers one and six are also factors of six. The numbers one, two, three and six are all factors of six.

Product, is the answer found when numbers are multiplied together. For example, the product of two and 10 is 20. And if three times five equals 15, then we can say that the product of three and five equals 15.

A multiple is a number, that is the product of a certain whole number and another whole number. For example, if we were looking for multiples of five, we could look at a five times table. Because all of the numbers down the right side after five, are multiples of five. So 10 is a multiple of five and so is 15, and so are 20 and 25. In fact, one of the curious and useful facts that you need to learn about numbers is that any number that ends in five or zero like these ones, is a multiple of five.