A man takes 18 days to finish a job, if he works with a man who is more efficient by half who long will it take them to finish the job?

Question

Vincent who is half as efficient as Eric takes 18 days to complete a task if he works alone. If Vincent and Eric work together how many days will it take them to complete the task?

Answer 1

By being more efficient by half I assume you mean it takes him half as long.

 

Y = amount of work to be done in the job.

 

The rate of work for each man is

 

A = Y/18.

B = Y/9.

 

Combining both of their efforts the combined work rate is:

 

Y/18 + Y/9 = Y/X. 

 

X will be the amount of time it takes for both of the men to complete the work together.

 

1/18 + 1/9 = 1/X -> 3/18 = 1/X -> X = 18/3 = 6.

 

It will take 6 days for the men to do the work together.