SOLUTION: Two companies working together can clear a parcel of land in 8 hours. Working alone, it would take Company A 2 hours longer to clear the land than it would Company B. How long wo

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Question 1162661: Two companies working together can clear a parcel of land in 8 hours. Working alone, it would take Company A 2 hours longer to clear the land than it would Company B. How long would it take Company B to clear the parcel of land alone? (Round your answer to the nearest tenth.)

Found 2 solutions by greenestamps, josgarithmetic:
Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


let x = # hours it takes B alone
then x+2 = # hours it takes A alone

1/x = fraction of job B does alone in 1 hour
1/(x+2) = fraction of job A does alone in 1 hour

Together the two do the job in 8 hours, so the fraction they do together in 1 hour is 1/8:

1%2Fx%2B1%2F%28x%2B2%29+=+1%2F8

Multiply by the common denominator, 8%28x%29%28x%2B2%29:

8%28x%2B2%29%2B8%28x%29+=+x%28x%2B2%29
16x%2B16+=+x%5E2%2B2x
x%5E2-14x%2B16+=+0

Solve using the quadratic formula or a graphing calculator (or any other method you might know)....

Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Maybe you can learn something from this one: https://www.algebra.com/algebra/homework/Average/Average.faq.question.1162637.html
https://www.algebra.com/algebra/homework/Average/Average.faq.question.1162637.html