SOLUTION: Joan takes 7 hours to clean the basement. It takes mike 12 hours to do this job. How long would it take if they worked together?
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Question 1148317: Joan takes 7 hours to clean the basement. It takes mike 12 hours to do this job. How long would it take if they worked together? Found 2 solutions by ikleyn, ankor@dixie-net.com:Answer by ikleyn(52888) (Show Source):
You can put this solution on YOUR website! Joan takes 7 hours to clean the basement.
It takes Mike 12 hours to do this job.
How long would it take if they worked together?
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Let t = time required working together
let the completed job = 1
Each will do a fraction of the job, the two fractions add up to 1 (completed job) + = 1
Get rid of the fractions, multiply by 84
84* + 84* = 84(1)
Cancel the denominators
12t + 7t = 84
19t = 84
t = 84/19
t = 4.421 hrs, or 4 + .421(60) ~ 4 hrs 25 min
