 This is a mathematical snack from the Association of Teachers of Mathematics. I have in front of me some coins. Can you see them? Fives, 20s, 50s, some one piece and two piece. I have no 10p coins. That's part of the challenge. I'm going to try and make exactly one pound using exactly 10 coins. Here I go. I'm going to start with 50, I'm going to use 220s, I'm going to use five and I'm going to bring in five ones. Let's count the amount. 50, 70, 90, 95, 96, 97, 98, 99, 100. Good. I've made a pound. Now let's count the number of coins. One, two, three, four, five, six, seven, eight, nine. I haven't used exactly 10 coins. I'm going to have another go and I'm going to start again. I'm going to have my 50 and this time I'm going to have 120. I'm going to bring in five fives and I'm going to get a two and three ones. Now let's count the amount. 50, 70, 75, 80, 85, 90, 95, 96, 97, 98, 99, 100. I've done it. Let's count the coins. One, two, three, four, five, six, seven, eight, nine, 10, 11. I still haven't done it in exactly 10 coins. Look, I'll leave that for you to do. Can you see how you might do it? I think when I do it again, I'm going to use something which will help me count the coins. So I'm going to use, perhaps just made this up, I'm going to use this which has got 10 spaces in it so I can put my coins in the 10 spaces and make sure I get the right number of coins. I'll leave it to you.