A, B, and C together can complete a task in 10 days. A alone takes 20 days, and B alone takes 30 days. How long will C alone take?
Show answer & explanation
Correct answer: D
Explanation
A + B + C = 10 days, A = 20 days, B = 30 days
A + B + C = 1/10
A = 1/20, B = 1/30
C = 1/10 − 1/20 − 1/30
= (6 − 3 − 2) / 60
= 1/60
Time = 60 days