SOLUTION: John can wash 7 cars in 3 hours and Kevin can wash 21 cars in 12 hours. If they work together, how many cars can they wash in 5 hours?
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Question 585355: John can wash 7 cars in 3 hours and Kevin can wash 21 cars in 12 hours. If they work together, how many cars can they wash in 5 hours? Answer by nerdybill(7384) (Show Source):
You can put this solution on YOUR website! John can wash 7 cars in 3 hours and Kevin can wash 21 cars in 12 hours. If they work together, how many cars can they wash in 5 hours?
5(7/3 + 21/12)
5(28/12 + 21/12)
5(49/12)
245/12
20.4
or, rounding to whole cars:
20 cars
