Directions: Analyze and Solve the following problems completely. Write your solution in a coupon bond. 1. The mean and standard deviation for the quality grade - point averages of a random sample of 36 college seniors are calculated to be 2.6 and 0.3 respectively. Find the a. 95% confidence interval for the mean of the entire senior class b. 99% confidence interval for the mean of the entire senior class 2. A sample of 10 measurements of the length of a chip gave a mean of 2.36 cm and a standard deviation of 0.06 cm. Find the a. 95% confidence limits b. 99% confidence limits 3. A researcher of a cardboard manufacturing company would like to know the estimated thickness of the cardboard a machine produces. How many cardboards should he measure if he wants to be 99% confident that the estimate is accurate to 1 mm. Study shows that the standard deviation is 3mm.
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### Problem 1: Confidence Intervals for the Mean #### Part a: 95% Confidence Interval ** Show more…
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