Paul got a box of 20 crayons for his birthday. During the school year he lost 4 crayons while he gave away 24 crayons to his friends. How many more crayons did he give to his friends than those he lost?
Paul got 20 crayons. 
He lost 4 crayons. 
That means he has 16 crayons left. 
He gave away 24 crayons to his friends. 
That means he gave away 8 more crayons to his friends than those he lost.