Explanation:

12 men       120 acres        36 days     

54 men           ?                 54 days

 As 12 men can reap 120 acres,

54 men will be able to reap more acres in 36 days,

120 acres of land was reaped, so in 54 days,

more land will be reaped.

Thus, the numbers of acres that can be reaped by 54 men in 54 days = 54/12 x 120 x 54/36 = 810 acres

Hence, option 3 is the correct answer.