SOLUTION: It takes Bob three hours to mow a lawn, and John can mow the same lawn in 2 hours. How long would it take the two of them working together to mow that lawn?

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Question 133977: It takes Bob three hours to mow a lawn, and John can mow the same lawn in 2 hours. How long would it take the two of them working together to mow that lawn?
Answer by solver91311(24713) About Me  (Show Source):
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If it takes Bob 3 hours to mow a lawn, then he can mow 1%2F3 of a lawn per hour. Likewise, John can mow 1%2F2 of a lawn per hour. Together they can mow 1%2F3%2B1%2F2=5%2F6 of a lawn per hour. So it will take 1%2F%285%2F6%29=6%2F5 hours for them to mow one lawn together. 6%2F5 hour is 1 and 1/5 hour is 1 hour and 12 minutes. An hour and a quarter if you give them a glass of lemonade when they are done.