Comparing Fractions With Different Denominators

Hi, I'm Brooke and in this video we're going to be looking at comparing fractions with equivalence. So in the first example, it's relatively easy to compare the two because the denominators are the same. So we just have to look at the numerator. 3/4 is greater than 1/4 because 3 is greater than 1. Let's have a look at an example where the denominators are not the same. So to help me, I've represented this using a bar model. Here you can see I've got 3, 8 and 1, 2. And it's clear to see that 1/2 is greater than 3, 8. But we could have worked that out using equivalence. I need to make both of the denominators the same to compare them. So I'm going to find an equivalent fraction for a half, which would be 4, 8. Now the denominators are the same. I can compare both of them. So I can see that 4, 8 is greater than 3, 8. At this point, we would be expecting pupils to apply their knowledge to a worded problem. So in this example we've got Jenny, who ate five, eight of her pizza, and Danny, who ate three quarters of his. And we're trying to find out who ate the most. So we're comparing the fractions 5, 8 and 3 quarters, and again we notice that the denominators are not the same. So I'm going to find an equivalent fraction with the denominator of eight. So six, eight is equal to three eighths. Now the denominators are the same. I can compare the two. I can see that 6, 8 is greater than 5, 8 because the numerator is bigger. Therefore Danny ate the most pizza. And that's how you compare fractions using equivalence.