Question: In an article appearing in Today’s Health a writer states that the average number of calories in a serving of popcorn is 75. To determine if the average number of calories in a serving of popcorn is different from 75, a nutritionist selected a random sample of 20 servings of popcorn & computed the sample mean number of calories per serving to be 78 with a sample standard deviation of seven.
[A] Calculate the z or t value of the sample test statistic.
[a] z = 1.916
[b] t = -1.916
[c] t = 1.916
[d] z = 1.645
[B] State the null & alternative hypotheses.
[A] H0: µ ≥ 75, H1: µ < 75
[B] H0: µ = 75, H1: µ > 75
[C] H0: µ = 75, H1: µ ≠ 75
[D] H0: µ ≤ 75, H1: µ > 75