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
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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
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Question 177902: 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 (+ or -) 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
(a) Construct a 90 percent confidence interval for the true mean weight.
x-bar = (sum of the number)/10 = 3.308
E = z = 1.645*0.1399/sqrt(10) = 0.0728
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90% CI; 3.308-0.0728-0.0728 < u < 3.308+0.0728
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(b) What sample size would be necessary to estimate the true weight with an error (+ or -) 0.03 grams with 90 percent confidence?
n = [z*s/E]^2
n = [1.645*0.1399/0.03]^2 = 7.67^2 is appox 50
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(c) Discuss the factors which might cause variation in the weight of Tootsie Rolls during manufacture.
I'll leave that to your imagination.
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Cheers,
Stan H.
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