SOLUTION: Raja can do a piece of work in 20 days , while Ramesh can finish it in 25 days. ramesh started working and Raja joined him after 10 days. The whole work is completed in ?

Algebra ->  Rate-of-work-word-problems -> SOLUTION: Raja can do a piece of work in 20 days , while Ramesh can finish it in 25 days. ramesh started working and Raja joined him after 10 days. The whole work is completed in ?      Log On


   

Question 994572: Raja can do a piece of work in 20 days , while Ramesh can finish it in 25 days. ramesh started working and Raja joined him after 10 days. The whole work is completed in ?
Found 2 solutions by josgarithmetic, stanbon:
Answer by josgarithmetic(39613) About Me  (Show Source):
You can put this solution on YOUR website!
The piece of work is one whole, 1.
RT=1 , uniform rate equation for doing one unit of work, relating rate and time.

Let t be the time for Raja to help in finishing the job.

Work that ramesh did alone: %281%2F25%29%2A10
Work that ramesh and Raja did in combination simultaneously: %281%2F25%2B1%2F20%29%2At

Altogether they did 1 piece of work.
highlight_green%28%281%2F25%29%2A10%2B%281%2F25%2B1%2F20%29t=1%29

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Raja can do a piece of work in 20 days , while Ramesh can finish it in 25 days. ramesh started working and Raja joined him after 10 days. The whole work is completed in ?
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Raja rate = 1/20 job/day
Ramesh rate = 1/25 job/day
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Equation:
10 days work by Ramesh + x days work by both = 1 job
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10(1/25) + [(1/20)+(1/25)]x = 1 job
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(2/5) + [(5+4)/100]x = 1 job
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0.40 + 0.09x = 1
0.09x = 0.60
x = 6 2/3 days
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Cheers,
Stan H.
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