The weight (in pounds) for a population of school-aged children is normally distributed with a mean...

The weight (in pounds) for a population of school-aged children is normally distributed with a mean equal to 138 ± 23 pounds (μ ± σ).Suppose we select a sample of 100 children (n = 100) to test whether children in this population are gaining weight at a 0.05 level of significance.

Part (a)
What are the null and alternative hypotheses?
H₀: μ = 138
H₁: μ < 138
H₀: μ = 138
H₁: μ ≠ 138
H₀: μ ≤ 138
H₁: μ > 138
H₀: μ ≤ 138
H₁: μ = 138
Part (b)

What is the critical value for this test?
Part (c)

What is the mean of the sampling distribution?
lb
Part (d)

What is the standard error of the mean for the sampling distribution?
lb

Solutions

Expert Solution

Part (a)

Correct option:

H0: 138

H1: 138

Part (b):

One Tail Right Side Test

= 0.05

From Table, critical value of Z = 1.645

So,

critical value for this test: 1.645

Part (c):

The mean of the sampling distribution: 138

Part (d):

Standard error of the mean for the sampling distribution = /

= 23/ = 2.3

orchestra answered 1 year ago

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