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The Wechsler IQ test has a normal shape with μ = 100 and σ = 15....

The Wechsler IQ test has a normal shape with μ = 100 and σ = 15. Describe the expected characteristics of the distribution of sample means for samples of n = 45. Mean = Standard error Shape = Still speaking of the Wechsler IQ test, if you take a random sample of n = 36 students, what is the probability that the sample mean will be between 96 and 104? Be careful about which formula you use. Still speaking of the Wechsler IQ test, if you take a random sample of n = 144 students, what is the probability that the sample mean will be between 96 and 104?

Expert Solution

Solution:

We are given:

Describe the expected characteristics of the distribution of sample means for samples of n = 45.

Shape = Normally distributed

Still speaking of the Wechsler IQ test, if you take a random sample of n = 36 students, what is the probability that the sample mean will be between 96 and 104?

We have to find

Using the z-score formula, we have:

Now using the standard normal table, we have:

Still speaking of the Wechsler IQ test, if you take a random sample of n = 144 students, what is the probability that the sample mean will be between 96 and 104?

We have to find

Using the z-score formula, we have:

Now using the standard normal table, we have:

milcah answered 3 months ago

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