A fourth grade class of 28 students is given a standardized math test. The mean score of the 12 boys is 25 with a standard deviation of 3. The mean score of the 16 girls is 24 with a standard deviation of 4. What is the standard error for the sampling distribution

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Answer:

The standard error for the sampling distribution is 1.323.

Step-by-step explanation:

Let X = scores of girls and Y = scores of boys.

The information provided is:

[tex]\bar x=24\\s_{x}=4\\n_{x}=16\\\bar y=25\\s_{y}=3\\n_{y}=12[/tex]

As the population standard deviations are not known, use a pooled standard deviation to estimate the standard error of the sampling distribution.

The formula of pooled standard deviation is:

[tex]S_{p}=\sqrt{\frac{s_{x}^{2}}{n_{x}^{2}}+\frac{s_{y}^{2}}{n_{y}^{2}}}[/tex]

Compute the standard error for the sampling distribution as follows:

[tex]SE=\sqrt{\frac{s_{x}^{2}}{n_{x}^{2}}+\frac{s_{y}^{2}}{n_{y}^{2}}}=\sqrt{\frac{4^{2}}{16}+\frac{3^{2}}{12}}=\sqrt{1+\frac{9}{12}}=\sqrt{\frac{21}{12}}=1.323[/tex]

Thus, the standard error for the sampling distribution is 1.323.