A can complete a work in 17 days and B can complete the same work in 32 days. If they work together, in how many days will the work be completed? MCQ with Answer and Explanation

Explanation:
Total work = 17 × 27 = 459 man-days. Required days = 459/21 = 21.86 days.

Explanation:
Total work = LCM(12, 15, 20) = 60 units. Efficiency of A = 5, B = 4, C = 3. Combined efficiency = 5 + 4 + 3 = 12 units/day. Time taken together = 60 / 12 = 5 days.

Explanation:
Combined rate = 1/24 + 1/18. Required time = 10.29 days.