A and B can complete a work in 12 days and 16 days respectively. Both work together for 3 days and then A leaves. How long will B take to complete the remaining work? MCQ with Answer and Explanation

Total work = LCM(12, 16) = 48 units. Efficiency of A = 4, B = 3. Combined efficiency = 7 units/day. In 3 days, work completed = 3 * 7 = 21 units. Remaining work = 48 - 21 = 27 units. Time taken by B to complete remaining work = 27 / 3 = 9 days.