The scores of a certain population on the Wechsler Intelligence Scale for children (WISC) are thought to be normally distributed with a mean and standard deviation of 10. The 95\% confidence interval for \mu is?

UkusakazaL 2021-08-09 Answered
The scores of a certain population on the Wechsler Intelligence Scale for children (WISC) are thought to be normally distributed with a mean and standard deviation of 10. A simple random sample of twenty -five children from this population is taken and each is given the WISC. The mean of the twenty-five score is x=104.32. Based on these data a 95% confidence interval for μ is computed.
The 95% confidence interval for μ is?
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Answers (1)

question2answer
Answered 2021-08-16 Author has 155 answers

Step 1
Given:
σ=10
x=104.32
n=25
Step 2
The 95% cocfidence interval for the mean is:
C.I.=x±Zα2×σn
From the Z table Zα2=1.96
=104.32±1.96×1025

=104.32±3.92
=(104.323.92, 104.32+3.92)
=(100.40, 108.24)
Answer: =(100.40, 108.24)

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