Question

A is thrice as productive as c. Together they can complete a job in 22.5 days. If b joins them after they have worked for 15 days then in how many days can they finish the rest of the job if b alone can do the job in 15 days?

Answer 1

Step-by-step explanation:

Given A is thrice as productive as c. Together they can complete a job in 22.5 days. If b joins them after they have worked for 15 days then in how many days can they finish the rest of the job if b alone can do the job in 15 days?    

• Given Let the productivity of C be m
• Now productivity of A = 3m
• Total productivity when working together will be 4m
• Now number of days is directly proportional to 1 / productivity
• So productivity of B / Productivity of A + C = number of days taken by A + C / number of days taken by B
• So productivity of B / 4 m = 22.5 / 15
• Also productivity of B = 6
• Now total productivity after B comes will be 4 m + 6 m = 10 m
• Therefore productivity of A + C / productivity of A + B + C = Number of days taken to complete remaining work by A + B + C / Number of days taken for remaining work by A + C
•                           So 4 m / 10 m = (number of days taken to complete remaining work by A + B + C) / 22.5 – 15
•       So 4m / 10 m = (A + B + C) / 7.5
•     Or 5 (A + B + C) = 15
•   Or A + B + C = 15 / 5 = 3
• Therefore number of days taken to finish the remaining work by A + B + C = 3 days.

Reference link will be

https://brainly.in/question/13331571