SOLUTION: X and y together can build a room in 25 days. they work together for 15 days and then Y goes away. X finishes the rest of the work in 20 days. How long would each take to finish th

Algebra ->  Rate-of-work-word-problems -> SOLUTION: X and y together can build a room in 25 days. they work together for 15 days and then Y goes away. X finishes the rest of the work in 20 days. How long would each take to finish th      Log On


   

Question 924087: X and y together can build a room in 25 days. they work together for 15 days and then Y goes away. X finishes the rest of the work in 20 days. How long would each take to finish the work separately.
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
In +15+ days, they will finish +15%2F25+=+3%2F5+ of the room
There is +2%2F5+ of the room left to build
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After Y goes away, X's rate of working is:
+%282%2F5%29+%2F+20+ rooms / days
+%282%2F5%29+%2F+20+=+1%2F50+
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Plug this result into equation for working together:
Let Y's rate of working = +1%2Fd+ rooms/days
+1%2F50+%2B+1%2Fd+=+1%2F25+
+1%2Fd+=+2%2F50+-+1%2F50+
+1%2Fd+=+1%2F50+
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Working separately, X and Y both
work at the rate of ( 1 room ) / ( 50 days )