Answer:
(e) I am 95% sure that the average income of college students is between $19,800 and $20,200.
Step-by-step explanation:
Confidence interval is given by mean +/- margin of error.
95% confidence interval for the average income of college students is given as $20,000 +/- $200
From the above expression,
mean = $20,000
margin of error (E) = $200
Lower limit = mean - E = $20,000 - $200 = $19,800
Upper limit = mean + E = $20,000 + $200 = $20,200
This means that I am 95% confident that the average income of college students is between $19,800 (lower limit) and $20,200 (upper limit).