Question: A can do a work in 15 days, B can do it in 20 days, and C can do it in 30 days. If all three work together, how long will it take to complete the work?
Options:
Correct Answer: 6
Solution:
A\'s rate = 1/15, B\'s rate = 1/20, C\'s rate = 1/30. Combined rate = 1/15 + 1/20 + 1/30 = 1/6. They will complete the work in 6 days.