Question

A can do a work in 6 days, B in 10 days and C in 15 days. A and B work for 3 days. How long will it take B and C to finish the work?

Answer 1

Given,

A can do a work in = 6 days

B can do it in = 10 days

C can do it in = 15 days

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A and B 1 day work = 1/6 + 1/10

= (10+6) / 60

= 16/60

= 4/15

Part of work completed by A and B in 3 days = 4/15 * 3 = 4/5

Part of work remaining = 1 - 4/5 = 1/5

1 day work of B and C together = 1/10 + 1/15

= (3+2) / 30

= 5/30

= 1/6

Hence B and C will complete whole work together in 6 days

B and C will complete 1/5 part of work in = 6/5

= 1 1/5 days

B and C will finish the work in 1 1/5 days.

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