A recent national survey reported that the general population gave the president an average rating of m= 60 on a scale of 1 to 100 with 1 being most unfavorable, and 100 most favorable. A reseracher at IC hypothesizes that IC students are more critcal of the president than the general population. She collects data on 10 IC students (below). at significance level of alpha=.05 test the one-tailed hypothesis that IC students are more critical than the population.

Question

sample ratings of president
44 50 24 45 39 57 25 90 78 54

Answer 1

With such a small sample, you need to use a t-test with 9 df., t<2.262 to be significant one-tailed at P = .05.

The process is similar to the one given in your later post.

Answer 2

Find the mean first = sum of scores/number of scores

Subtract each of the scores from the mean and square each difference. Find the sum of these squares. Divide that by the number of scores to get variance.

Standard deviation = square root of variance