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antoniya [11.8K]
3 years ago
14

A random sample of 28 items is drawn from a population whose standard deviation is unknown. The sample mean is x=900 and the sam

ple deviation is s = 10. Use appendix D to find the values of student's t. (a) Construct an interval estimate of u with 98% confidence. (Round your answers to 3 decimal places.)
Mathematics
1 answer:
tatiyna3 years ago
7 0

Answer:

<em>795.596≤u≤804.403</em>

Step-by-step explanation:

Confidence interval is expressed using the formula;

CI = xbar ± (z*s/√n)

xbar is the sample mean

z is the z score at 98% confidence

s is the standard deviation

n is the sample size

Given

xbar = 800

z = 2.33

s = 10

n = 28

Substitute into the formula;

CI =800 ± (2.33*10/√28)

CI = 800 ± (2.33*10/5.2915)

Ci = 800± (2.33* 1.8898)

CI = 800 ± 4.4033

CI = (800-4.4033, 800 + 4.4033)

CI = (795.596, 804.403)

<em>Hence an interval estimate of u with 98% confidence is expressed as </em>

<em>795.596≤u≤804.403</em>

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It looks like you want to compute the double integral

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Convert to polar coordinates, in which <em>D</em> is given by the set

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