Question

2. You randomly select and measure the lengths of 34 bolts. The sample mean length is...

2. You randomly select and measure the lengths of 34 bolts. The sample mean length is 1.24 inches and the standard deviation is 0.3 inches. Construct a 94% interval of confidence of the mean length of all bolts.

Find a point estimate for the mean length of all bolts

Verify that the conditions are met to construct an interval of confidence for the mean length of all bolts

Calculate the critical Z value to construct a 94% confidence interval (round to 3 decimals)

Calculate the standard of error (round to 4 decimals)

Calculate the margin of error to construct the 94% confidence interval (round to 4 decimals)

Construct a 94 % confidence interval of the mean length of all bolts (round to 4 decimals)

Interpret the interval of confidence

Math   Statistics-And-Probability   
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Answer #1

1) The point estimate for the mean length of all bolts is 1.24 inches

2) Sample size n > 30 so the sample is large, large sample follows normal distribution

3)

The 94% chance that the mean length of all bolts is lies between 1.14322 and 1.33678

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