stu had a lot of baseball cards. one day he decided to give half of them to his brother seth. then he gave one third of what he had left to a friend. then he gave half of what was left to another friend. stu now has 50 baseball cards. how many did he start with?
Work backwards. 50X2X(3/2)X2=?
what do you mean by (3/2)???
Because he gave away a third at that point. What was left was two thirds; working backwards you're doing the inverse of everything. Where he gave away half his cards, multiply by two. When he gave away a third, he had two thirds left, multiply by the inverse of that to get 3/2. It's a tricky part of the problem, but when you plug in 300 it works.
So its 300 cards?
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