A and B can do a piece of work in 30 days, while B and C can do the same work in 24 days and C and A in 20 days. They all work together for 10 days when B and C leave. How many days more will A take t
A). 11 days
B). 13 days
C). 15 days
D). 18 days
18 days
2 ( A + B + C) ‘s 1 day’s work = 1/30 + 1/24 + 1/20 = 1/8
their 1 day’s work = 1/8/2 = 1/16
their 10 days work = 1/16 × 10 = 5/8
the remaining work = 3/8
A’s 1 day’s work = 1/16 – 1/24 = 1/48
Therefore, the No. of days A alone will take to complete 3/8 of the work = 3/8/ 1/48
= 3/8 × 48 = 3 × 6 = 18 days.