# Video: GCSE Mathematics Foundation Tier Pack 2 • Paper 1 • Question 5

GCSE Mathematics Foundation Tier Pack 2 • Paper 1 • Question 5

02:06

### Video Transcript

Evaluate four cubed.

So the first thing to consider with this question is what is four cubed do actually tell us; what does it mean? Well, four cubed means four multiplied by four multiplied by four. It is not four multiplied by three. This is a really common mistake that students make. They see four cubed or they can have two to the power of five and they just multiply the two numbers together. And this is a common mistake like I said. This is not the case.

Okay, so we got four multiplied by four multiplied by four. So here I’ve got a tip. A tip is to try and actually learn or you square numbers up to 12 squared and also all you cube numbers for five cubed to help us with questions like this. So for example, do you know that one cubed is one, two cubed is eight, three cubed is 27, four cubed is 64, and five cubed is 125.

So using what we could remember, we’d know the answer to this question would just be 64. Like I said, it’s really useful. I mean for a question like this, we can actually work out and I am gonna show you how you can actually calculate it. Particularly, when we got multistage problems, it saves you a step of calculations.

Okay, so we think it’s gonna be 64. So let’s try and show that with a calculation. So now, we get that four cubed is gonna be equal to 16 multiplied by four and that’s because four multiplied by four is 16.

Okay, great, so now what we want to do is actually multiply these together. And the way you do that is using any one of our multiplication methods. I’ve just set it up using the column method.

So first of all, we multiply four and six. So therefore, this gives us 24. So I put the four in the units column and then carry the two into the tens column. Then, I have four multiplied by one, which gives me four. Then, I add on the two that I carried from earlier, which gives me six. So I put this into the tens column.

So with that calculation, we can confirm that four cubed is equal to 64. And that was the same using our calculation method and also like I said earlier with the values that we should remember and that’s one of our cube numbers up to five cubed.