A, B and C can individually complete a task in 24 days, 20 days and 18 days, respectively. B and C start the task, and they work for 6 days and leave. The number of days required by A alone to finish the remaining task, is:

$8 \frac{4}{5}$ days

A = 24 days, 

B = 20 days,

C = 18 days,

⇒ B + C worked for 6 days = (18 + 20) x 6 = 38 x 6 = 228 units   ..(Efficiency × Days = Total work)

⇒ Remaining work = 360 - 228 = 132 units.

⇒ Time required by A to complete 132 units of work = \(\frac{132}{15}\) = \( { 8}_{ 15}^{12 }\) = \( { 8}_{ 5}^{4 }\) days.       ..(\(\frac{Work}{Efficiency}\) = Time)