40 men can complete a work in 15 days. Three days after they started working, 20 more men joined them. In how many days the total work will be completed?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 11
Concept used:
Work = Number of people × number of days
Calculations:
⇒ Total work = 40 × 15 = 600 units
40 men worked for 3 days, work done = 40 × 3 = 120 units
Remaining work = 600 - 120 = 480 units
20 more men joined the work, total men = 40 + 20 = 60
Time taken = 480/60 = 8
Total time = 3 + 8 = 11 days