A and B can do a piece of work in 5 days and 10 days, respectively. They began the work together, but A left after some days and B finished the remaining work in 8 days. After how many days did A leave?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e.
Given:
A and B can do a piece of work in 5 days and 10 days, respectively.
Calculations:
Total work (LCM of 5, 10) = 10 units
Efficiency of A = 10/5 = 2
Efficiency of B = 10/10 = 1
Let A left the work after D days
According to the question;
⇒ (A + B) × D + B × 8 = 10
⇒ 3D + 8 = 10
⇒ 3D = 10 - 8 = 2
⇒ D = 2/3