Important information about Z test for mean
Not what you're looking for?
Please provide an explanation and step by step process on how these answers are chosen.
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 and computed the sample mean number of calories per serving to be 78 with a sample standard deviation of 7.
State the null and alternative hypotheses.
A. H0:  = 75, H1:  ≠ 75
B. H0:  ≤ 75, H1:  > 75
C. H0:  ≥ 75, H1:  < 75
D. H0:  = 75, H1:  > 75
Compute 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
At the  = .05 level of significance, does the nutritionist have enough evidence to reject the writer's claim?
A. No
B. Yes
C. Cannot determine
Purchase this Solution
Solution Summary
The solution provides step by step method for the calculation of Z test statistic for mean . Formula for the calculation and Interpretations of the results are also included.
Purchase this Solution
Free BrainMass Quizzes
Measures of Central Tendency
This quiz evaluates the students understanding of the measures of central tendency seen in statistics. This quiz is specifically designed to incorporate the measures of central tendency as they relate to psychological research.
Terms and Definitions for Statistics
This quiz covers basic terms and definitions of statistics.
Know Your Statistical Concepts
Each question is a choice-summary multiple choice question that presents you with a statistical concept and then 4 numbered statements. You must decide which (if any) of the numbered statements is/are true as they relate to the statistical concept.
Measures of Central Tendency
Tests knowledge of the three main measures of central tendency, including some simple calculation questions.