First, you would divided 270 by 15
270 ÷ 15 = 18
Then, you would divide 18 by 2 because it only takes half an hour to sell 15.
18÷2 = 9
Therefore, it would take 9 hours!
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Another Way!
First, multiply 15 by 2 because it only takes half an hour to sell 15.
15×2 = 30
Then, divide 270 by 30!
270÷30 = 9
Therefore, it would take 9 hours!