A can do a piece of work in 24 days. B in 15 days and C in 12 days. In how many days can A finish the work if he is assisted by B on one day and C on the next, alternately?	Choose the correct answer
A) 8 2/5days
B) 10 2/5days
C) 6 2/5days
D) 18 2/5days
E) 17 2/5days
8 2/5days + B = 1/24 + 1/15 = 13/120   8 2/5days + C = 1/24 + 1/12 = 1/8   13/120 + 1/8 = 28/120   4 1/5 days * 2 = 8 2/5days   8 2/5daysNSWER:8 2/5days
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A can do a piece of work in 24 days. B in 15 days and C in 12 days. In how many days can A finish the work if he is assisted by B on one day and C on the next, alternately?