18 men can do a piece of work in 20 days. After working for 8 days, they get a notice to complete the work 4 days earlier than originally scheduled. How many more men will be required to be hired to complete the work as per the new schedule?

9

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 values in the formula,

⇒ 18 x 12 = (18 + M) x 8

⇒ M = 9.