P can do a work in 19.5 days. Q can do the same work in 13 days and R can do the same in 6.5 days. Q

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17 Aug 2017 Time and Work

P can do a work in 19.5 days. Q can do the same work in 13 days and R can do the same in 6.5 days. Q and R start the work and leave after 4 days. P finishes the remaining work in X days. What is the value of X?

OPtion

1) 2.5 days
2) 2.0 days
3) 1.75 days
4) 1.5 days
5) 2.25 days
6) 4.5 days
7) 5 days
8) 5.5 days
9) 6.0 days
10) None of these

Solution

Amount of work done by Q and R in 4 days = 4*(1/13 + 1/6.5) = 12/13

Amount of work remaining after 4 days = 1/13

Amount of work done by P in 1 day = 1/19.5
So for 1/19.5 work P takes 1 day
Hence for 1/13 work P would take (1/(1/19.5))*1/13 = 1.5 days

Correct Option: 4 Best Solution (7)