SOLUTION: A random sample of 10 miniature Tootsie Rolls was taken from a bag. Each piece was weighed on a very accurate scale. The results in grams were
3.087 3.131 3.241 3.241 3.270 3.353
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-> SOLUTION: A random sample of 10 miniature Tootsie Rolls was taken from a bag. Each piece was weighed on a very accurate scale. The results in grams were
3.087 3.131 3.241 3.241 3.270 3.353
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Question 179648: A random sample of 10 miniature Tootsie Rolls was taken from a bag. Each piece was weighed on a very accurate scale. The results in grams were
3.087 3.131 3.241 3.241 3.270 3.353 3.400 3.411 3.437 3.477
(a) Construct a 90 percent confidence interval for the true mean weight. (b) What sample size
would be necessary to estimate the true weight with an error of ± 0.03 grams with 90 percent confidence?
(c) Discuss the factors which might cause variation in the weight of Tootsie Rolls during
manufacture. Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! A random sample of 10 miniature Tootsie Rolls was taken from a bag. Each piece was weighed on a very accurate scale. The results in grams were
3.087 3.131 3.241 3.241 3.270 3.353 3.400 3.411 3.437 3.477
x-bar = 3.305 ; s =0.132.. ; n= 10
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(a) Construct a 90 percent confidence interval for the true mean weight.
E = 1.645[0.132/sqrt(10)] = 0.069..
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90% CI: 3.305-0.069 < u < 3.305+0.069
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(b) What sample size would be necessary to estimate the true weight with an error of ± 0.03 grams with 90 percent confidence?
n = [z*s/E]^2 = [1.645*0.132/0.03]^2 = 52.39; rounding up n = 53
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(c) Discuss the factors which might cause variation in the weight of Tootsie Rolls during manufacture.
humidity level; machine variability; manufacture tolerance
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Cheers,
Stan H.
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