1.12

National STEM Learning Centre

Skip to 0 minutes and 7 secondsPAULA KELLY: OK, so we've just seen how fractions can be written as mixed numbers. Another way to write some fractions, if we come back to our examples-- if we had our two pizzas, in our full pizza, we have 8 out of 8 slices. In our next pizza, we have a 5 out of 8 slices. So we can also write that as having 13/8. In our other example, we had two full pizzas-- so 5 out of 5 slices, another 5 out of 5 slices, and then finally, 3 out of 5 slices remaining. So all together, we have 13/5. So these fractions where the numerator is larger than the denominator we call top-heavy fractions.

Skip to 0 minutes and 51 secondsWe can also call that improper, or vulgar fractions. They're all examples where fractions have a value greater than 1.

Top heavy fractions

Most fractions students encounter represent a number which is less than one whole, and are of the form where the numerator has a value which is less than the value of the denominator.

We have seen how fractions with a value greater than one can be expressed as a mixed number. Another way of expressing a fraction with a value greater than one is as a top heavy fraction: one where the numerator has a greater value than that of the denominator. These are also known as improper fractions.

Problem worksheet

Now complete questions 12 to 15 from this week’s worksheet.

Teaching resource

To explore mixed numbers and top heavy (improper) fractions further, see the Fractions: Mixed numbers video showing conversion between mixed numbers and top heavy fractions.