Q2. The breaking strengths in pounds of ten specimens of manila rope were found to be 660, 460, 630, 430, 540, 610, 580, 550, 400 and 560. a) Estimate the mean breaking strength of rope made in this way and find a 95% confidence interval for the mean, assuming the specimens are drawn from a normal population. Explain what this confidence interval represents. [4 marks] b) Estimate the weight at which 5% of such specimens would be expected to break. [2 marks] c) The producer claims that the mean strength of rope is 600 pounds. A consumer suspects that the mean is less than 600. Use an appropriate test to test the producer's claim against the consumer's at 5% significance level. State your hypotheses and give your conclusion. [4 marks]
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Step 1: Calculate the mean breaking strength of the rope: Given breaking strengths: 660, 460, 630, 430, 540, 610, 580, 550, 400, 560 Mean = (660 + 460 + 630 + 430 + 540 + 610 + 580 + 550 + 400 + 560) / 10 Mean = 5220 / 10 Mean = 522 Show more…
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