SOLUTION: Joy can do a job in 7 hours, while it takes Lucy only 5 hours to do same job. How long will it take them to do the same job if they work together?
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-> SOLUTION: Joy can do a job in 7 hours, while it takes Lucy only 5 hours to do same job. How long will it take them to do the same job if they work together?
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Question 989005: Joy can do a job in 7 hours, while it takes Lucy only 5 hours to do same job. How long will it take them to do the same job if they work together?
You can put this solution on YOUR website! Joy can do a job in 7 hours, while it takes Lucy only 5 hours to do same job.
How long will it take them to do the same job if they work together?
:
let t = time required when working together
let the completed job = 1
:
A shared work equation, each will do a fraction of the job, the two fractions add up to one + = 1
multiply by the least common factor of 7 and 5, 35:
35* + 35* = 35
Cancel the denominators
5t + 7t = 35
12t = 35
t = 35/12
t = 2 hrs which is 2 + *60 = 2 hrs 55 min
