Atrade magazine routinely checks the drive through service times of fast food restaurants. a 90% confidence interval that results from examining 653 customers in one fast food chains drive through has a lower bound of 178.2 secinds and an upper bound of 181.6 seconds.

what does this mean?

a.) one can be 90% confident that the mean deive through serivce time of this fast food chain is 179.9 seconds.

b.) the mean drive through service time of this fast food chain is 179.9 seconds 90% of the time.

c.) there is a 90 % probability that the mean drive through service time of this fast food chain is between 178.2 seconds and 181.6 seconds.

d.) one can be 90% confident that the mean drive through service time of this fast food chain is between 178.2 seconds and 181.6 seconds.

d) one can be 90% confident that the mean drive through service time of this fast food chain is between 178.2 seconds and 181.6 seconds.

Step-by-step explanation:

The interpretation of 90% confidence interval says that a person can be 90% confident that the true population mean lies in it.

Given : A 90% confidence interval that results from examining 653 customers in one fast food chains drive through has a lower bound of 178.2 seconds and an upper bound of 181.6 seconds.

i.e.  90% confidence interval for population mean drive through service time of fast food restaurants is between 178.2 seconds and 181.6 seconds.

It means a person can be 90% confident that the mean drive through service time of this fast food chain is between 178.2 seconds and 181.6 seconds.

Hence, the correct answer is option d) .one can be 90% confident that the mean drive through service time of this fast food chain is between 178.2 seconds and 181.6 seconds.

f(x) has value 150 at x= 0

and 0 at x= 3

so d(f(x))/dt = slope = -150/3 = -50