Step 1
Given; Suppose that shoe sizes of American women have a bell-shaped distribution with a mean of 8.04 And a standard deviation of 1.53.
Required; using the empirical rule what percentage of American women have shoe sizes that are less than 11.1. please do not round your answer.
Step 2
The empirical rule states that for a normal distribution, 68% of the distribution are within one standard deviation from the mean, 95% are within two standard deviations from the mean and 99.7% are within three standard deviations from the mean.
Given that:
[tex]\begin{gathered} mean(\mu)=8.04 \\ Standard\text{ deviation\lparen}\sigma)=1.53 \\ \end{gathered}[/tex]
68% are within one standard deviation
[tex]\mu\pm\sigma=8.04\pm1.53=(6.51,9.57)[/tex]
95% are within two standard deviation
[tex]\mu\pm2\sigma=8.04\pm2(1.53)=(4.98,11.1)[/tex]
Thus, we can see that the American women have shoe sizes that are no more than 11.1 will be;
[tex]95\text{\%+\lparen}\frac{100-95}{2})\text{\%=95+2.5=97.5\%}[/tex]
Answer;
[tex]The\text{ American women with a shoe size that are less than 11.1=97.5\%}[/tex]