40 men can complete a piece of work in 18 days. 9 days after they start working together, 5 more men join them. How many days will they now take to complete the remaining work?

8 days

Formula to be used here,

\( { M}_{1 } \) x \( { D}_{1 } \)  = \( { M}_{2 } \) x \( { D}_{2 } \)

where, M = No. of Men, D = No. of Days,

⇒ Putting in the values,

⇒ 40 x 9 = 45 x \( { D}_{2 } \)

⇒ \( { D}_{2 } \) = 8 days,