SOLUTION: I have six answered but not sure if its right. im stuck on number y 6. Heights of men have a mean of 176 cm and a standard deviation of 7 cm. (based on the data from the National

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Question 853023: I have six answered but not sure if its right. im stuck on number y
6. Heights of men have a mean of 176 cm and a standard deviation of 7 cm. (based on the data from the National Health Survey). Use the range rule of thumb to estimate the minimum and maximum “usual” heights of men. Charles Darwin had a height of 182 cm. Is Darwin’s height unusual?
my answer 176-2(7)= 162; 176+2(7)=190, I put that his height is not unusual

7. Heights of men have a bell-shaped distribution. Using the Empirical Rule, what is
the approximate percentage of men between
a. 155 cm and 197 cm?

b. 169 cm and 183 cm?
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

mean of 176 cm and a standard deviation of 7 cm

182 cm, z = 6/7, < than 1 SD from mean,  agree with You.    

between

 a. 155 cm and 197 cm? between 3 SDs from mean ⇒ 99.7%



 b. 169 cm and 183 cm? between 1 SD from mean ⇒ 68% (sometimes 68.3 is used)



For the normal distribution: 

one  standard deviation from the mean accounts for about 68% of the set 

two standard deviations from the mean account for about 95%

and three standard deviations from the mean account for about 99.7%.

Important to Understand z -values as they relate to the Standard Normal curve:

Below:  z = 0, z = ± 1, z= ±2 , z= ±3 are plotted.  

Note: z = 0 (x value the mean) 50% of the area under the curve is to the left and %50 to the right