Answer :
Answer:
B's 1 day work =1/25
B's 5 day work =1/25x5
After B leaves,remaining work =1-1/5=4/5
Since,A+C finishes the work in 5 days
therefore,work done= efficiency × no of days
which will be 4/5=efficiency ×5
efficiency =4/25
so,the no of days required to build wall will be 25/4
Step-by-step explanation: