Ram and Shyam can complete a task in 
days and 15 days, respectively. They work together for 4 days, and then ram leaves. In how many days after Ram leaves, will Shyam complete the remaining task alone?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e 2 days
Let the number of units of work be 60.
The number of units works done by Ram = 60 / (20 / 3)
⇒ 9 units
The number of units works done by Shyam = 60 / 15
⇒ 4 units
The number of units works completed in 4 days = 4 ×(4 + 9)
⇒ 4 × 13 = 52 units
Rest work = 60 - 52 = 8units
⇒ Shyam will take number of days = 8 / 4 = 2days