If boys and girls are equally likely, groups of 400 births have a mean of 200 girls and a standard deviation of 10 girls. Is 232 girls in 400 births an unusually high number of girls?

Answer:

Step 1 of 1</p>

Using the range rule of thumb to find the minimum usual value μ – 2σ and the maximum usual value μ – 2σ.

minimum: mean - 2(standard deviation)

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