Good question
BunuelSharing my solution below-
The approach to solving this question would be-
1. Identify the amount of work completed by all of them together (in 3 days, since they are not working simultaneously, but one after another)
2. Calculate the number of days taken in all to complete the work
3. Identify the ratio of work done by each one of them
4. Divide the payment received by them in the ratio of the work done by them
A completes 1/90 work in 1 day (on Day 1)
B completes 1/40 work in 1 day (on Day 2)
C completes 1/12 work in 1 day (on Day 3)
Together they complete 43/360 work together in 3 days
So in 24 days, they complete (43*8)/360 work= 344/360 work= 43/45 work
Remaining work left= 2/45= 4/90 work
On the 25th day, A will work again and complete 1/90 work.
Remaining work= 4/ 90- 1/90= 3/90 work
On the 26th day, B will work and complete 1/40 work.
Remaining work= 3/ 90- 1/40= 1/120 work
On the 27th day, C will complete the work
C takes to complete 1 work= 12 days
Hence, C takes to complete 1/120 work= 12 * 1/120 day= 1/10 day
So total days taken= 26+1/10 days
Now, lets identify the work done by all three (ratio of work)=
A worked for 9 days
B worked for 9 days
C worked for 8+1/10 days
Ratio of work done by A:B:C= 9*1/90 : 9*1/40 : 81/10*1/12 = 1/10 : 9/40 : 27/40= 4:9:27
Total payment made to them= $360
Let's divide the money in the same ratio as work done to arrive at the answer=
A:B:C= 4/40*360 : 9/40*360 : 27/40*360= 36:81:243
(Answer-- Option B)