This question seems confusing, but once you draw bar models, it becomes easy to understand. This video shows a step by step solution using bar models.doraemo wrote:please help :

1) The ratio of the number of marbles May, Teddy and Sam had was 3:5:2. During a game, May lost half of her marbles to Teddy. Teddy lost 20 marbles to Sam who then had 3 times the number of marbles May had at the end of the game.

a) What was the percentage increase in the number of marbles Sam had at the end of the game?

b) How many marbles did Teddy have at the end of the game?

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