A and B, working together, can complete a work in d days. Working alone, A takes (8 + d) days and B takes (18 + d) days to complete the same work. A works for 4 days. The remaining work will be completed by B alone, in:
Answer & explanation
Correct answer: option 1
A + B = d days
A = (8 + d) days,
B = (18 + d) days,
⇒ d = √(8 x18) = √144 = 12
⇒ d = 12, therefore, A = 8 + 12 = 20 days. B = 18 + 12 = 30 days,
⇒ A worked for 4 days = 3 x 4 = 12 days,
⇒ Remaining work = 60 - 12 = 48 units,
⇒ Time taken by B to complete the work = \(\frac{48}{2}\) = 24 days. ..(\(\frac{Work}{Efficiency}\) = Time)