Why do this problem?
would be useful when the group are looking at balancing weights and using grams and kilos. It requires some clear thinking and some calculation but should not take long to do.
Which weighs more - the apple or the weights?
How many weights are there? So how will you find out how heavy one weight is?
Learners could work out similar problems when there are five weights rather than four.
All learners will benefit from using real scales to weight items before tackling this problem, so what is involved becomes clearer.