Sarah has 2 trees in her backyard. the elm tree’s current height is 38 inches. it grows 4 inches each year. the oak tree is 45.5 inches tall and grows 2.5 inches per year. how long will it take for the two trees to be the same height?

38 + 4 = 42 (1 year); 42 + 4 = 46 (2 years); 46 + 4 = 50 (3 years); 50 + 4 = 54 (4 years); 54 + 4 = 58 (5 years)
45.5 + 2.5 = 48 (1 year); 48 + 2.5 = 50.5 (2 years); 50.5 + 2.5 = 53 (3 years); 53 + 2.5 = 55.5 (4 years); 55.5 + 2.5 = 58 (5 years)
It will take 5 years before the trees are the same height, 58 inches. 

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