SOLUTION: Bobby and Mike have a summer job mowing the school yard once a week. The school provides them with two riding lawn mowers.One mower requires 7 hours to mow the school yard, while t

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Question 266027: Bobby and Mike have a summer job mowing the school yard once a week. The school provides them with two riding lawn mowers.One mower requires 7 hours to mow the school yard, while the other could cover the school yard in 6 hours. How long will the job take using both mowers? (Round your answer to the nearest tenth.)
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
The first mower can mow 1%2F7 of the yard in 1 hour.
The second mower can mow 1%2F6 of the yard in 1 hour.
Together, they can mow 1%2F7+%2B+1%2F6+=+13%2F42 of the yard in 1 hour.
So it would take them 42%2F13 hours to mow the entire yard.
42%2F13+=+3.2307 hours.
Rounded to the nearest tenth this would be 3.2 hours.