Answer:
In this scenario, the solution for n is determined to be 16 when rounded up to the closest integer
Step-by-step explanation:
The following information has been provided for this case:
symbolizes the population standard deviation
signifies the preferred margin of error
The formula for the margin of error of the actual mean is given as:
(a)
In this case, the margin of error (ME) is 0.03, and to find n, we rearrange equation (a) to get:
(b)
With a confidence level of 80%, and the significance level being 
and 
, the critical value is 
. Plugging in these values into formula (b) results in:
Thus, the solution for this situation results in n=16, rounded to the nearest whole number
The initial time was 15.7 minutes.
Explanation of steps:
Let x represent the initial time (in minutes).
The relay team is working on minimizing their relay race duration.
First, they cut down their time by 2.1 minutes.
Afterwards, they manage to reduce that time by 10 percent.
If the concluding time ends up being 3.96 minutes, then
x-t1-t2= 3.6
x= 3.6+ t1+ t2
x= 3.6+ 2.1+ 10
x= 15.7
Thus, their starting time was 15.7 minutes.
