Answer:
So the answer for this case would be n=247 rounded up to the nearest integer
Step-by-step explanation:
We know that the standard deviation is :
represent the deviation
The margin of error is given by this formula:
(a)
And on this case we have that ME =25 and we are interested in order to find the value of n, if we solve n from equation (a) we got:
(b)
The critical value for 95% of confidence interval now can be founded using the normal distribution and the critical value would be , replacing into formula (b) we got:
So the answer for this case would be n=247 rounded up to the nearest integer