When Tyler runs the 400 meter dash, his finishing times are normally distributed with a mean of 76 seconds and a standard deviation of 2.5 seconds. Using the empirical rule, determine the interval of times that represents the middle 99.7% of his finishing times in the 400 meter race

So then we expect the 99.7% of the finishing times would be between 68.5 s and 83.5 s for the 400 meters race

Step-by-step explanation:

Let X the random variable who represent the finishing times.

From the problem we have the mean and the standard deviation for the random variable X.

So then the parameters are

On this case in order to check if the random variable X follows a normal distribution we can use the empirical rule that states the following:

The probability of obtain values within one deviation from the mean is 0.68 , within two deviations we have 0.95  and within 3 deviations from the mean is 0.997

And from this rule we have 99.7 % of the values within 3 deviations from the mean, so we can find the limits like this:

So then we expect the 99.7% of the finishing times would be between 68.5  s and 83.5 s for the 400 meters race