Problem 4CQQ
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
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)
= 200 - 2(10)
= 180
maximum: mean + 2(standard deviation)
= 200 + 2(10)
= 220
Yes the result of 232 girls in 400 births unusually high of girls.