2 Diets Developers of diets like to advertise that their die

2. Diets. Developers of diets like to advertise that their diets produce significant weight loss results. A new diet has been developed and several studies were done to investigate the effectiveness of the diet. In each study the average number of pounds lost was of interest, and researchers would like to show that dieters lost a significant amount of weight. (a) Identify the appropriate null and alternative hypotheses to test the researchers? claim. Write the correct answer and then select the best answer online. (b) Suppose that an average weight loss of 1 pound (x = 1) and standard deviation of s = 7 pounds were found in each of the following studies. Further, assume weight loss is normally distributed. For each case, compute the test statistic, find the approximate p-value , and make a decision about the null hypothesis using an a = 0.05 level of significance. Round t statistics to two decimals. i. a sample of size n = 10 was used

Solution

Let mu1 be the average weight before new diet and mu2 after new diet

H0: mu1 =mu2

Ha: mu1 > mu2

b) Average for mu1-mu2 =1 and sigma = 7

Std error = 7/rt 10 = 2.213

t = 1/2.213 = 0.4517 = 0.45