Houghton Mifflin Harcourt Algebra 1, 2015
HM
Houghton Mifflin Harcourt Algebra 1, 2015 View details
4. Normal Distributions
Continue to next subchapter

Exercise 16 Page 343

Find the difference between the mean height and the given height in terms of standard deviations.

97.5 %

Practice makes perfect

We have been told that the heights of adult males are normally distributed with a mean of 72 inches and a standard deviation of 2 inches. We will find the probability that randomly chosen man is less than 76 inches tall. x≤ 76inches First, let's find the difference between 76 inches and the mean. 76 inches- 72 inches= 4 inches Then, we will divide the difference by the standard deviation. 4 inches/2 inches=2 Thus, 76 inches is 2 standard deviations above the mean. To find the probability, we will shade the data that is no more than 2 standard deviations above the mean.

Finally, we can find the probability that a randomly chosen man is less that 76 inches tall by adding the percentage of data in the shaded regions.

p=0.15 %+2.35 %+13.5 %+34 %+34 %+13.5 %
p=97.5 %

The probability that a randomly chosen man is less than 76 inches is 97.5 %