Shannon painted 2/5 of her room and her sister Lauren painted 1/2 of the room. Shannon says that they now have 3/7 painted. Is Shannon correct?

Answer 1

2/5 + 1/2 = 4/10 + 5/10 = 9/10 = 0.9 = 90%, which incidentally is 63/70

vs

3/7 = 30/70

So no, Shannon is incorrect. You may NOT add the bottom numbers.

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