A, B, and C can complete a piece of work in 24 days, 40 days, and 60 days, respectively. In how many days was the piece of work completed?
(1) A, B, and C started working together, and A continued to work till the end.
(2) A, B, and C started working together, B and C left the work 2 days and 7 days, respectively, before the completion of the work.
The OA is B.
Can someone please tell me if my approach is correct or not and if I am solving it right or not?
A's one day work =1/24
B's one day work =1/40
C's one day work =1/60
Working together for first 2 days = (1/24 + 1/40+ 1/60) *2
A and C Working together for next 5 days = (1/24 + 1/60) *5
A working alone for rest of the days = (1/24)*x
(1/24 + 1/40+ 1/60) *2 + (1/24 + 1/60) *5 + (1/24)*x = 1
and we can find x by this? Thanks in advance!
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A, B, and C can complete a piece of work in 24 days, 40 days
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BTGmoderatorLU
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Jay@ManhattanReview
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Hi,BTGmoderatorLU wrote:A, B, and C can complete a piece of work in 24 days, 40 days, and 60 days, respectively. In how many days was the piece of work completed?
(1) A, B, and C started working together, and A continued to work till the end.
(2) A, B, and C started working together, B and C left the work 2 days and 7 days, respectively, before the completion of the work.
The OA is B.
Can someone please tell me if my approach is correct or not and if I am solving it right or not?
A's one day work =1/24
B's one day work =1/40
C's one day work =1/60
Working together for first 2 days = (1/24 + 1/40+ 1/60) *2
A and C Working together for next 5 days = (1/24 + 1/60) *5
A working alone for rest of the days = (1/24)*x
(1/24 + 1/40+ 1/60) *2 + (1/24 + 1/60) *5 + (1/24)*x = 1
and we can find x by this? Thanks in advance!
Your approach is fine. Upon solving (1/24 + 1/40+ 1/60) *2 + (1/24 + 1/60) *5 + (1/24)*x = 1, you will bget the unique value of x. This is a linear equation, thus, only one value of x will result. Sufficient.
-Jay
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