alleryThree painters take 12, 15 and 20 days alone. If all three work together, the job takes
A3 days
B4 days
C5 days
D6 days
Answer & Solution
Correct answer: C. 5 days
Daily work is (5 + 4 + 3)/60 = 12/60 = 1/5 of the job, so 5 days.
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