Antony and Vikash together can complete a piece of work in 20 days and Vikash alone can complete it in 25 days. In how many days can Antony alone complete the same work?

100 days

Antony(A) + Vikash(V) = 20 days,

Vikash(V) = 25 days,

⇒ A + V = 5,  (Efficiency)

⇒ A + 4 = 5,

⇒ A = 1,

⇒ Time requires by Antony to complete the total work = \(\frac{100}{1}\) = 100 days,  ..(\(\frac{Work}{Efficiency}\) = Time)