A can do a work in 15 days and B in 23 days. In how many days will they complete 75% of the work together? MCQ with Answer and Explanation

Explanation:
Total work (LCM of 10, 12, 15) = 60 units. Efficiencies: A = 6, B = 5, C = 4. Total combined efficiency = 6 + 5 + 4 = 15 units/day. Time taken = 60 / 15 = 4 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 = 1/15 + 1/25. Time = 9.38 days.