# Percentage of an amount using a mobile phone battery

- Author:
- Mark Horley

See if you can work out how much time you have left on your battery....
1, Start with all boxes unticked and drag the little blue dot at the top of the battery left and right. Try to estimate the percentage represented by the pink area.
2, Tick the first box to see if you were right.
3, Now tick the second box and change the slider to set the total (I.e. time when fully charged) to something not too tricky - maybe 200 mins?
4, Can you work out the time remaining on the battery?
5, Tick the third box to see if you were right.
6, Untick the third box and repeat 4 and 5 each time sliding the battery to a few different percentages. Once you've got the hang of that, change the total and try some more.