If 45 persons can complete a work in 18 days, working 8 hours a day, then how many persons are required to complete two-thirds of the same work in 20 days, working 9 hours a day?

24

Formula to be used here,

\(\frac{M_1\;×\;D_1\;×\;H_1}{M_2\;×\;D_2\;×\;H_2}\) = \(\frac{W_1}{W_2}\)

where, M = No. of men, D = no. of Days, H =No. of hours, W = Unit of work

⇒ Putting values into the formula

⇒ \(\frac{45\;×\;18\;×\;8}{M_2\;×\;20\;×\;9}\) = \(\frac{1}{2/3}\)

⇒ \( { M}_{2 } \) = 24.