A can do a piece of work in 10 days, while A and B together can complete it in $2\frac{1}{2}$days. How long will B alone take to complete the work?
Answer & explanation
Correct answer: option 2
A = 10 days,
A + B = \( { 2}_{ 2}^{ 1} \) days,
⇒ Efficiency = A +B = 4, A =1
Simplifying, we get, Efficiency of B = 3.
⇒ Time taken by B to complete the work alone = \(\frac{10}{3}\) days ..(\(\frac{Work}{Efficiency}\) = Time )