What is the minimum "usual" value equal beats per minute?

Question

A certain group of tests subject had pulse rates with a mean of 77.1 beats per minute and standard deviation of 12.6 beats per minute. Would it be unusual for one of the test subjects to have a pulse rate of 82.3 beats per minute?

Answer 1

Hello, thank you for taking the time to post your question!

No, it’s inside of one standard deviation of the mean value so it would not be considered unusual

Z = (82.3 – 77.1) / 12.6 = 5.2 / 12.6 = 0.41 , meaning that it is well within the typical range for this group

I hope that helps you get moving in a better direction on this type of question! Feel free to reach out if you have any additional questions beyond that :)

Answer 2

Hi, Danny!

 

This question requires a little bit of background in statistics.  According to statistics, when data is represented using a standard bell-shaped curve (also known as a "Normal Distribution"), 68.2% of the data should fall within 1 standard deviation of the mean; 95.2% of the data should fall within 2 standard deviations of the mean; and 99.7% should fall within 3 standard deviations of the mean.  Typically, anything beyond 2.5 or 3 standard deviations away from the mean would be considered "unusual."  In this case, 82.3 beats per minute definitely falls within 1 standard deviation of the mean (77.1 ± 1SD = 77.1 ± 12.6 -->64.5-89.7), so I would consider 82.3 bpm to be a common pulse rate.

 

For a visual of this idea and for more information about normal distributions, visit http://www.mathsisfun.com/data/standard-normal-distribution.html.

 

Good luck!

 

Patty