Question

You find that the average income for college students is $20,000 +/- $200 (with a confidence level of 95%). Indicate the CORRECT interpretation(s) of this finding below (you may select more than one).
a.I am 95% certain that the average income for college students is $20,000.
b.If the same sampling and statistical procedures are conducted 100 times the true population mean will be encompassed between $19,800 and $20,200 (and 5 times it will not).
c.5% of college students make less than $19,800.
d.95% of college students make more than $20,200.
e. I am 95% sure that the average income of college students is between $19,800 and $20,200.

Answer 1

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).