Question

The time taken by a randomly selected applicant for a mortgage to fill out a certain form has a normal distribution with

mean value 10 min and standard deviation 2 min. If five

individuals fill out a form on one day and six on another,

what is the probability that the sample average amount of

time taken on each day is at most 11 min?​

Answer 1

Answer:

Now, there are obviously more variables but this is where it starts to get a bit confusing for me. In the first part of the problem, X clearly refers to the time it takes to fill out a single form. But in the second part of the problem, the population (n=5) fills out a different number of papers on each day, changing the population the question at the end of the problem is addressing. Presumably, there is some other population Y and I'm looking for P(Y¯¯¯¯≤11). Figuring out what population Y encompasses and how to set up the solution is where I'm stumped. Any nudge in the right direction is greatly appreciated.