A diet claims to help lose weight. A dietician wants to see if a particular diet helps lose weight. 120 people were on the diet
for 6 months. After 6 months, the sample mean of weight loss was 0.8 pound with sample SD of 2 pounds. The distribution is more or less normal. What kind of hypothesis testing do we use
Options are <em>"a. z-test for proportions, b. z-test for means, c. none of the other three answers, d. t-test for means"</em>
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Sample size = n = 120
Sample mean = x = 0.8
Sample standard deviation = s = 2
Claim: A particular diet helps loss weight.
<u>Hypothesis test</u>
The null and alternative hypothesis is
H0 : μ = 0
Ha : μ < 0
Now, when population standard deviation is unknown we use t-test otherwise use z-test. So, the kind of hypothesis testing that we use is t-test for means.