Using Bar Models For Multiplicative "Times Bigger" Problems

Hi, my name's Ben. And in this video we're going to be using the bar model to look at how we can solve complex comparison problems involving division. Here's our question. Mum and dad both have money in their pockets. Dad has five times less than Mum has. The difference between the amounts is £48. How much money do they both have? Let's look at representing this through the bar. We know that dad has an amount. We know that Mum has five times more than that amount because it says here that dad has five times less. So the inverse of five times less will be five times more. Mum has five times more than dad. We can represent that as a bar, too. It's important that each section, each part of the bar is roughly proportional, because that will help. Now, we know from looking at the question that the difference between them is £48. So these four sections here are worth £48 altogether. So if we do 48 divided by four, we get 12. So each one of these parts here is worth 12. And if those four are worth 12, so will these. And then we can work out how much money each of them have. So dad has £12. A mum has five lots. 1, 2, 3, 4, 5 of £12, 2, which is 12 times 5, which is £60. And that's how we can use the bar model to solve complex problems involving division.