We are trying to test whether a new low fat diet actually helps obese people lose weight. 150 randomly obese people are assigned to group 1 and put on a low-fat diet. Another 150 people are assigned to group 2 and put on a diet of approximately the same amount of food, but not as low in fat. After 6 months, the mean weight loss was 24pounds for group 1 with a standard deviation of 7 pounds, and for group 2 the mean weight loss was 20 pounds with a standard deviation of 5 pounds. Is the low fat diet more effective? Perform a hypothesis test at the 1% significance level. a) Define the parameters b)Test statistics c)P-value approach

We are trying whether, a new low fat diet actually helps obese people lose weight. 100 randomly obese people are assigned to group 1 and put on a low fat-diet. another 100 people are assigned to group 2 and put on a diet of approximately the same amount of food, but not as low in fat. After 4 months, the mean net weight loss was 9.31 pounds for group 1 with a standard deviation of 4.67 pounds, and for group 2 the mean net weight loss was 7.40 pounds with a standard deviation of 4.04 pounds. Is the low-fat diet more effective? Perform a hypothesis test at the 5% significance level a) Define Parameters and state null and alternative hypothesis b) Find test statistics c) Find p-value d) Conclusion

Fran is training for her first marathon, and she wants to know if there is a significant difference between the mean number of miles run each week by group runners and individual runners who are training for marathons. She interviews 37 randomly selected people who train in groups, and finds that they run a mean of 47.7 miles per week. Assume that the population standard deviation for group runners is known to be 3.3 miles per week. She also interviews a random sample of 49 people who train on their own and finds that they run a mean of 49.4 miles per week. Assume that the population standard deviation for people who run by themselves is 4.4 miles per week. Test the claim at the 0.10 level of significance. Let group runners training for marathons be Population 1 and let individual runners training for marathons be Population 2.   Step 2 of 3 :   Compute the value of the test statistic. Round your answer to two decimal places.

What is the normalized z-score for a data point that has a value of 50 if the mean (Mu) is 560 and sigma is 55? This data point is taken from a total of 800 data point values .

A new drug is being tested to see if it reduces the frequency of migraines.  Study participants were divided into two groups.  49 participants in group 1 received the medication; 42 participants in group 2 received a placebo.  After a period of six months, group 1 had a mean of 4 migraines.  It is known that the population standard deviation for this group is 1.3 migraines.  Group 2 had a mean of 5.4 migraines.  The population standard deviation for this group is 1.7 migraines.  Can we conclude that the medication reduces the population mean number of migraines?  Use αα =0.01.  Note: If t-test, then unequal variances are assumed. Question a)Let:     μ1μ1 = the population mean number of migraines with the medication           μ2μ2 = the population mean number of migraines with the placebo (Step 1) State the null and alternative hypotheses by selecting the appropriate symbol, and identify which tailed test:     H0:H0: μ1μ1         μ2μ2     H1:H1: μ1μ1         μ2μ2     Which tailed test…

Fran is training for her first marathon, and she wants to know if there is a significant difference between the mean number of miles run each week by group runners and individual runners who are training for marathons. She interviews 42 randomly selected people who train in groups and finds that they run a mean of 47.1 miles per week. Assume that the population standard deviation for group runners is known to be 4.4 miles per week. She also interviews a random sample of 47 people who train on their own and finds that they run a mean of 48.5 miles per week. Assume that the population standard deviation for people who run by themselves is 1.8 miles per week. Test the claim at the 0.01 level of significance. Let group runners training for marathons be Population 1 and let individual runners training for marathons be Population 2.   Step 2 of 3 :   Compute the value of the test statistic. Round your answer to two decimal places.

Researchers want to compare the relative effectiveness of two popular diets. They randomly assign each of 400 volunteers to one of two Groups: A & B.  There are 200 volunteers in each group. Group A spends 6 months on Diet A. Group B spends 6 months on Diet B.   At the beginning of the study, the difference in average weight between the two groups was negligible. After the study, the Group A had lost on average 7.8 pounds with a standard deviation of 13.4 pounds, while the Group B had lost on average 5.3 pounds with a standard deviation of 14.8 pounds. Determine the z-score/test statistic for a two-tailed test with significance level α = 0.05 , accurate to 2 decimal places.

This question applies to the next 3 MCQs. Wire wound resistors are being custom made for a Design House with a maximum specification of 305.70 ohms and a minimum specification of 304.55 ohms. If the resistance is higher it can be reworked, if lower they must be scrapped. The resistors manufactured follow a normal distribution with a mean of 305.2 ohms and a standard deviation of 0.25 ohms. What percentage of the resistors are scrap (approximately)? 5% 2% 0.1% 0.5% 1%

There are many ways to measure the reading ability of children. One frequently used test is the DRP or Degree of Reading Power. The national average score in DRP test is 32. We want to determine if there is sufficient evidence at the 5% level to suggest that the mean score of all third graders in YOUR district is higher than the national mean. The DRP scores for a simple random sample of 41 third graders in that suburban school in YOUR district yielded a mean of 35.2. Assume that the population of DRP scores of third graders in that suburban school district are normally distributed with a population std.dev of 11.

The ACCUPLACER is a college readiness exam. The scores for the math section are normally distributed with a mean of 75 and standard deviation of 8. A college policy is that the bottom 15% of test takers are required to take a remedial math course over the summer. Students who score below what score will have to take the summer course?