Question

Please use MATLAB.

Part B (Based off week 11 workshop content) An engineering company has ordered steel to be used for a rail construction project. Before using the steel, they want to test it to ensure the material properties from the supplier are correct A random sample of the ordered steel is tested for its Yield Strength. The results are shown below. Yield Strength (MPa) 197203194196196197198205 1. Calculate the sample mean and sample variance by hand, then verify your answers with MATLAB's mean and var functions. 2. The supplier claims that the average Yield Strength of their steel is 200 MPa. Conduct a hypothesis test to determine whether there is enough evidence to reject this claim using a significance level of α- 0.05 3. Determine a 95% confidence interval for the average Yield Strength. Does the confidence interval support the result of your hypothesis test? 4. Use the ttest function in MATLAB to verify your answers to Q2 and 3 5. If we were to double the sample size and obtain the same sample mean and sample variance, what would happen to the 95% confidence interval for Yield Strength? Explain why this happens

Answer 1

aktion Siell Strength CMPa 19구 203 194 196 196 134 198 205 チ = 198-57148 mple Voriance (194-198.5귀43六(203-1985귀43)v-t (20S + 98,STIYe 93千1485千 enple Vorance = 15.6,905 MATLAB CODE; [19チ, 203, 199, R&197, 2057 meonCx) anguer: 198.5チ ansuer 15.619

廾a J)//.200 chon Reon The Sigconce Test Stoabistc 98.25-200 /Jh 3 #0183477 - -1 313 Dersion about nulf rgotes'ろ 'nce it込observed th d !tle l、3132 te z 2.365 The P-valis p o236,and Since po.23062 o 0s it込conducted that the nau hy others n not regected

__-Fe 's concluded that 4he naungku ther i t erugh eudooe to clai thal Tes Poalaton mean u d.efet en 200, ct The O- 5 Sign cance 2 3.4013 3. 152454 198.25(MPa) ー :,95% con ence interno, 30

Since The internal indudes The Value ao。ая, result oP The phypothesis test an The Magin CL=(98.25 ±t 二198.25 ± 2-132 x 3거7018 198.25 20095