Aresearcher draws a population of 40 adults from a city and administers an iq test (which is known to have a population mean of 100 and population standard deviation of 15). his sample mean is 108. what is the 95 percent confidence interval for this result?

Step-by-step explanation:

According to the given information, we have

n= 40

Critical z-value for 95% confidence =

Confidence interval :

Hence, the 95 percent confidence interval for this result :

option: d is correct

step-by-step explanation:

45

step-by-step explanation:

to find a percentage, add a decimal in front and multiply it by the other number.

.25 times 180= 45