Answer: the interval of heights that represents the middle 95% of male heights from this school is between 66 inches and 76 inches.
Step-by-step explanation:
Let x be a random variable representing the heights of males from this school. With the mean and standard deviation given, then the Empirical Rule says the that
1) About 68% of the x values lie between 1 standard deviation below and above the mean.
2) About 95% of the x values lie between 2 standard deviations below and above the mean.
3) About 99.7% of the x values lie between 3 standard deviations below and above the mean.
From the information given,
mean = 71 inches
Standard deviation = 2.5 inches
We want to determine where 95% of x values lies. This is 2 standard deviations from the mean Therefore,
2 standard deviations = 2 × 2.5 = 5 inches
The heights are
71 - 5 = 66 inches and
71 + 5 = 76 inches
