Answer:
5.347
Step-by-step explanation:
5.3471075307175.
It is not. 9w x 0 is 0, then 0-12 is -12.
Answer:
Simon takes approximately 13.76 hours to complete the job alone.
Step-by-step explanation:
We are given the following in the question:
Kamila can do a job in 26 hours
So, part of work done by Kamila in 1 hour =

Simon and Kamila working together can do the same job in 9 hours
.
So, (Simon and Kamila)'s 1 hour work =

So, Simon's 1 hour work =

So,
Simon can do
part of work in hour = 1
Time taken by Simon to complete the job alone =

Thus, Simon takes approximately 13.76 hours to complete the job alone.
5 is the mean of variable a I might be wrong