A and B can finish a piece of work in 12 days and 18 days respectively. A starts the work and they work alternately, then in how many days will the work be completed?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is Option 2 i.e. .
Let the total work = (LCM of 12 and 18) = 36 units
Efficiency of A = 36/12 = 3 unit
Efficiency of B = 36/18 = 2 unit
As they work on alternate days,
Work completed in 2 days
⇒ 2 days = 3 unit + 2 unit
⇒ 2 days = 5 unit
⇒ 14 days = 35 unit
The remaining work = 36 - 35 = 1
On the last day, A has to work = 1/3 days
Total days = 14 days + 1/3 days = days
Hence, The total work is completed in days