SOLUTION: if a man completes a work in 9 days,second man complete work in 7 days and 3 mens together complete a work in 3 days,in how many days does the third man completes the work alone?
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Question 621042: if a man completes a work in 9 days,second man complete work in 7 days and 3 mens together complete a work in 3 days,in how many days does the third man completes the work alone? Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! if a man completes a work in 9 days,
A second man complete work in 7 days
and 3 men together complete a work in 3 days,
in how many days does the third man completes the work alone?
:
let t = time required by the 3rd man to complete the job
Let the completed job = 1
:
A typical shared work equation
: + + = 1
Multiply by 63t, to clear the denominators
63t* + 63t* + 63t = 63t*1
Cancel the denominators
7t(3) + 9t(3) + 63(3) = 63t
:
21t + 27t + 189 = 63t
48t + 189 = 63t
189 = 63t - 48t
189 = 15t
t = 189/15
t = 12.6 days required by the 3rd man
:
:
Check this on a calc: enter (3/9)+(3/7)+(3/12.6)
