Question

Periodically, a town water department tests the the drinking water of homeowners for contaminants such as lead. The lead levels in water specimens collected for a sample of 10 residents of the town had a mean of 2.8 mg/L and a standard deviation of 2.7 mg/L. Complete parts a through c.

**a.** Construct a 90% confidence interval for the
mean lead level in water specimens from the town.

**b**. Interpret the interval in terms of this
application. Choose the correct answer below.

A. The water department can be 10% confident that the mean lead level in drinking water for all residents in the town is within this interval.

B. The water department can be 90% confident that the mean lead level in drinking water for all residents in the town is 2.8mg/L.

C. The water department can be 90% confident that the mean lead level in drinking water for all residents in the town is within this interval.

D. The water department can be 90% confident that the mean lead level in drinking water for all residents in the town is outside this interval.

E. The water department is confident that 90% of the mean lead level in drinking water for all residents in the town is described by this interval.

**c.**The phrase "90% confidence interval" means
that if many intervals were constructed using the same methods and
the same ____________________ then____% of those intervals would
contain the true _________________.

Answer #1

Periodically, a town water department tests the the drinking
water of homeowners for contaminants such as lead. The lead levels
in water specimens collected for a sample of 10 residents of the
town had a mean of 3.1 mg/L and a standard deviation of 1.6 mg/L.
Complete parts a through c.
a.Construct a 90% confidence interval for the mean lead level
in water specimens from the town.
left parenthesis nothing comma nothing right parenthesis,
(Round to three decimal places as...

Periodically, a town water department tests the the drinking
water of homeowners for contaminants such as lead. The lead levels
in water specimens collected for a sample of 10 residents of the
town had a mean of 3.2 ?mg/L and a standard deviation of 2.9 ?mg/L.
Complete parts a through c.
a. Construct a 90?%confidence interval for the
mean lead level in water specimens from the town.

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2.8
2.4
2.8
3
3
2.9
2.3
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b) What must be true in order to construct a...

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Question 5: You work for the consumer insights
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