Arun alone can finish a work in 12 days and Shama alone can do it in 15 days. How much time will be taken to finish the work, if Arun and Shama work together?
Answer & explanation
Correct answer: option 4
Arun = 12 days,
Shama = 15 days,

⇒ Arun + Shama can compllete the work in = \(\frac{60}{(5 + 4)}\) = \(\frac{60}{9}\) = \( { 6}_{ 9}^{ 6} \) = \( { 6}_{ 3}^{ 2} \) days.