# Video: GCSE Mathematics Foundation Tier Pack 3 • Paper 2 • Question 4

GCSE Mathematics Foundation Tier Pack 3 • Paper 2 • Question 4

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### Video Transcript

List all the factors of 16.

So the first thing about this question is to actually think about this word “factor.” So what are factors? Well, factors are numbers you multiply together to get another number. For example, we could say the first two factors of 16 are one and 16 and that’s because one multiplied by 16 is equal to 16. The next pair of factors are gonna be two and eight and that’s because two multiplied by eight gives us 16.

Again with either of these pairs, it could work the other way around cause eight multiplied by two would be 16 and 16 multiplied by one would be 16. Well, then, we could try the next number up, which will be three. Well, three doesn’t actually go into 16 cause if we list the three times table or the multiples of three, we get three, six, nine, 12, 15, then 18. So 16, it doesn’t go into. So it isn’t a factor of 16.

Well then, our final factor of 16 is actually going to be four. And it’s just four because it’s four multiplied by four to get 16. So four squared is 16. We know that this is the final factor because actually as we’ve got four multiplied by four. If we were to go higher than four, then we’d actually have to multiply it by a number less than four. As we’ve already checked out one, two, and three and we know whether they are factors or not, we don’t need to go any further.

So therefore, we can say that all the factors of 16 are one, two, four, eight, and 16.