This activity is designed to be accessible to primary school pupils at Key Stage 2.
Detailed teachers' notes for this activity are available on our NRICH website.
Stage: 2 Challenge Level:
Ben is hoping to enter the long jump at his school sports day.
One day I saw him manage quite a good jump.
However, after practising several days a week he finds that he can jump half as far again as he did before.
This last jump was $3.75$ metres long.
So how long was the first jump that I saw?
Now Mia has been practising for the high jump.
I saw that she managed a fairly good jump, but after training hard, she managed to jump half as high again as she did before.
This last jump was $1.20$ metres.
So how high was the first jump that I saw?
How did you work these out?
Can you find any other ways of finding a solution?
Which way do you prefer? Why?
If you're finding hard to get started, try looking at this hint.
Detailed teachers' notes for this activity are available on our NRICH website, where you can also find thousands more mathematical resources including problems, investigations and games for all ages from 5 to 19..