MasteryExams
Quantitative Aptitude • Time, Speed & WorkEasy

A can finish a piece of work in 18 days and B can finish it in 36 days. How many days will they take working together?

A. 18 days
B. 54 days
C. 27 days
D. 12 days✓ Correct Answer

💡 Solution & Explanation

In one day A does 1/18 of the work and B does 1/36. Together they do 1/18 + 1/36 = 1/12 of the work per day. So the whole work takes 12 days. Shortcut: ab ÷ (a + b) = 648 ÷ 54 = 12. Together they must be faster than either one alone.

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