Ratio practice: sharing and simplifying

To share an amount in a ratio, add the parts to find the total, divide the amount by that total to find one part, then multiply out each share. Sharing 72 pounds in the ratio 3 to 5 gives 8 parts worth 9 pounds each, so the shares are 27 pounds and 45 pounds.

Ratio compares quantities. Sharing an amount in a given ratio is one of the most reliably examined topics at GCSE Foundation, and the method is short enough to master in an afternoon.

The method, step by step

1. Add the parts. A ratio of 3:5 has 8 parts in total.
2. Find one part. Divide the total amount by the number of parts.
3. Scale each share. Multiply one part by each side of the ratio.
4. Check. The shares should add back to the original total.

Worked example

Common mistakes

Practise this every day

MathsDaily gives you twenty fresh questions a day across the whole curriculum, with new numbers generated every morning. Questions on this topic appear regularly in the daily set, alongside a plain-English tip and a video link if you get stuck.

Start today’s 20 →

Related topics