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2 years ago

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A random sample of 12 men age 60-65 has a mean blood pressure of 142. 3 mmHg and a standard deviation of 20.8 mmHg. Construct a

99% confidence interval for the standard deviation of all men age 60-65.

1 answer:

Over [174]2 years ago

3 0

Answer:

The 99% confidence interval = (126.93,157.67)

Step-by-step explanation:

The formula for Confidence Interval =

Mean ± z × Standard deviation /√n

Mean = 142. 3 mmHg

Standard deviation = 20.8 mmHg.

n = 12

Z score for 99% confidence interval = 2.56

Confidence Interval =

142.3 ± 2.56 × 20.8/√12

142.3 ± 2.56 × 6.0044427996

142.3 ± 15.371373567

Confidence Interval

= 142.3 - 15.371373567

= 126.92862643

≈ 126.93

142.3 + 15.371373567

= 157.67137357

≈ 157.67

Therefore, the 99% confidence interval = (126.93,157.67)

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###

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