A can finish a piece of work in 12 days and B in 18 days. How many days will they take working together?

A. 7.5 days

B. 15 days

C. 6 days

D. 7.2 days

Doubtly AI Asked 27 Oct 2026 AI-generated · not yet verified ssc cgl Save WhatsApp Report

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Answer: D. 7.2 days

Answer: (D) 7.2 days

Shortcut: together = \(\frac{ab}{a+b} = \frac{12 \times 18}{30} = 7.2\) days.

LCM method: work = 36 units; A does 3/day, B 2/day, together 5/day → 36 ÷ 5 = 7.2 days.

Doubtly AI · 27 Oct 2026 AI-generated · not yet verified Report

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