A is three times as efficient as B. Working together, they finish a job in 36 days. How many days would A take to finish the job alone?

💡 Solution & Explanation

If B does 1 unit of work per day, A does 3 units, so together they do 4 units per day. The whole job is 4 × 36 = 144 units. A alone takes 144 ÷ 3 = 48 days, and B alone would take 144 days. A, being faster, needs fewer days than B but more than the 36 days they take together.