SOLUTION: I need help with this please;
If a farmer uses a large tractor, she can plow a field in 8 hours. Her sister, using a smaller tractor, can plow the same field in 12 hours. How
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If a farmer uses a large tractor, she can plow a field in 8 hours. Her sister, using a smaller tractor, can plow the same field in 12 hours. How
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Question 537277: I need help with this please;
If a farmer uses a large tractor, she can plow a field in 8 hours. Her sister, using a smaller tractor, can plow the same field in 12 hours. How many hours would it take to plow the field if they worked together? Express your answer as a mixed number. Answer by richwmiller(17219) (Show Source):
You can put this solution on YOUR website! x/f+x/s=1
f=8
s=12
every hour the farmer does 1/8 of the job
We know that together they can do it in less than 8 hours since the farmer can do it alone in 8 hours
x/8+x/12=1
x=24/5 or 4.8 hours working together.
24/5/8+24/5/12=1
3/5+2/5=1
5/5=1
or
4.8/8+4.8/12=1
.6+.4=1
1=1
ok
