A can finish a piece of the work in 16 days and B can finish it in 12 days. They worked together for 4 days and then A left. B finished the remaining work. For how many total days did B work to finish the work completely?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 9
A can finish a piece of the work = 16 days
B can finish it =12 days
Their total work = LCM of 16 and 12 = 48 unit
Efficiency of A = 48/16 = 3
Efficiency of B = 48/12 = 4
So, according to the question
Thier 4 days work = (3 + 4) × 4 = 28 unit
Remaining work done by B = (48 - 28)/4 = 5 days
So, the total number of days did B work to finish the work completely = 4 + 5 = 9 days