30 men can complete a piece of work in 24 days. 12 days after they started working together, 10 more men joined them. How many days will they now take to complete the remaining work?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 9 days
According to the question,
Total work = 30 × 24 = 720 units
One day work of 30 men = 1/24 units
12 days work of 30 men = 12 × 1/24 = 1/2 units
12 days later 10 more men joined them,
Total no. of men = 30 + 10 = 40 men
Half of the work is done by 30 men then remaining work = 720/2 = 360 units
Time required to complete 360 units of work by 40 men = 360/40 = 9 days