Question 777803
Amar can do a piece of work in 15 days. when he had worked for 3 days, sameer joined him and the remaining work was finished in 8 days. in how many days can sameer alone finish the whole work? 
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let x=days sameer can finish the whole work alone
1/x = his work rate
1/15=amar's work rate
..
Amar worked for 11 days
Sameer worked for 8 days
..
11*1/15+8*(1/x)=100%
11/15+8/x=1
8/x=1-11/15=4/15
4x=8*15=120
x=30
days sameer can finish the whole work alone=30