SOLUTION: 2 men and 3 women working 7 hours a day finish a work in 5 days. 4 men and 4 women working 3 hours a day do the same work in 7 days. Find the number of days in which the work is do
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-> SOLUTION: 2 men and 3 women working 7 hours a day finish a work in 5 days. 4 men and 4 women working 3 hours a day do the same work in 7 days. Find the number of days in which the work is do
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Question 1039507: 2 men and 3 women working 7 hours a day finish a work in 5 days. 4 men and 4 women working 3 hours a day do the same work in 7 days. Find the number of days in which the work is done by 7 men only working 4 hours a day? Answer by solver91311(24713) (Show Source):
If the job is done in 5 days at 7 hours per day, then the whole job is done in 35 hours. Hence, of the job is done in one hour by 2 men and 3 women. So if represents the fraction of the job done by one man in one hour, and represents the fraction of the job done by one woman in one hour, we can say:
Using similar analysis:
First, solve the 2X2 system. I recommend the elimination method. Multiply the first equation by -20 and the second by 15:
Then add
Since we want to know about a scenario where only men are working on the job we don't need to solve for .
Since one man does of the job in one hour, 7 men do of the job in one hour. Therefore they need to work 20 hours to get the whole job done. If they work 4 hours per day, then it will take 5 days.
John
My calculator said it, I believe it, that settles it
