A alone can complete a work in 40 days. 20 percent of the same work will be completed by A in how many days?

8 days 10 days 5 days 6 days

8 days

A = 40 days, Let's assume efficiency of A as 1. ⇒ Therefore Total work = 1 x 40 = 40 units  ..(Efficiency × Days = Total work) ⇒ 20% of 40 = 8 units. ⇒ So, time required for A to complete 8 units of work = \(\frac{8}{1}\) = 8 days.