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project - the proportion was 36% however with 93%...

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Project 3 Engineering Statistics 1. In this experiment we want to see whether the mean life exceeds 540 hours or not with a level of significance of .015. Since we know the statistic is a Z-distribution then we went ahead and calculated the Z value to be 2.17 to compare against. If the statistic gives us a value above 2.17 then we have enough evidence to move away from the Null Hypothesis which is the mean does not exceed 540. Then we proceeded to calculate the Z-value of this distribution, Test of mu = 540 vs > 540 The assumed standard deviation = 20 95% Lower Variable N Mean StDev SE Mean Bound Z P C1 15 551.33 14.81 5.16 542.84 2.19 0.014 From this we got that the Z value is above 2.17, meaning that the mean indeed does exceed 540. We can also check this because the 95% Confidence Interval Lower bound is 542, which is still above 2.17. 2. In this statistic there were 18 damaged helmets out of 50 tested helmets. In this sample
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Unformatted text preview: the proportion was 36% however with 93% confidence interval we can say that in a longer running test it would be between 23.7% and 49.75% 3. For this experiment since I determined the samples to be independent from each other since they are two different types of plastic pipe. The first thing we have to determine is whether of not the means of the two samples are significantly different. We should declare that if they are more than 10% different then they are significantly different. After running our test we determined that the P-value is .253, since it is bigger than 10%. Also with 97% Confidence Interval we can determine that the difference of the average deflection is between (-4.09, 12.62). I noticed that the difference interval is higher on the positive side, this means that it is skewed 3 times to the side of the first sample. Therefore the first sample contains a higher mean than the second one....
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project - the proportion was 36% however with 93%...

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