Age 11 to 16
In estimation questions don't be afraid to have a go with a guess
at some numbers in the problem and then to refine your estimate
after checking it makes some sort of sense.
Although there is no 'right' answer to an estimation, there are
good or bad estimations and sensible or over detailed calculations.
Think how you might make your estimation a good one, and think how
it makes sense to ignore certain complexities in the