SOLUTION: I have a problem how to set up word problems example do i multiply or divide when to add or subtract etc. the question is tractors a,b,c,d,are identical and are pulling identical p

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Question 857421: I have a problem how to set up word problems example do i multiply or divide when to add or subtract etc. the question is tractors a,b,c,d,are identical and are pulling identical planting machines. Working together a,b, and c can plant 270 acres of soybeans in 3 hours. At this rate, how many acres can a,b,c, and d, all working together, plant in 5 hours. Can you please show me how to start and explain how you got the answer

Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
Each of the four tractors plant at the same rate. You are given THREE of these identical tractors plant 270 acres in 3 hours. Again since these tractors are identical and work at the same rate each, the 270%2F3 acres/hour rate is three times bigger than for just a single tractor.

T is the rate of 1 tractor.
You have highlight_green%28T%2BT%2BT=270%2F3%29 in units of acres per hour.
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3T=270%2F3
T=270%2F%283%2A3%29
T=%283%2A3%2A3%2A10%29%2F%283%2A3%29
highlight_green%28T=30%29 acres per hour, for ONE tractor.
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Now, your question is like 4T for all four of these identical tractors; and you want to know how many acres are planted in 5 hours.
highlight%28%284T%29%2A5=%284%2A30%29%2A5%2A%28acres%2Fhour%29%2Ahour=120%29 acres