SEARCH HOME
 Math Central Quandaries & Queries
 Question from Kenneth: Hello: What is a common calculation used to determine percentiles? For example, five employees have the following salaries: Office worker 1 - $\$25,000$Office worker 2 -$\$27,000$ Office worker 3 - $\$30,000$Office worker 4 -$\$32,000$ Office worker 5 - $\$35,000$What is the percentile rank of office worker 3 who earns$\$30,000?$ Here's what I know: Add the number of salaries. Total: 5 Add the smallest number of salaries less than $\$30,000.$There are two. Now, divide 2 by 5 and multiply by 100.$\large \frac25 \normalsize \times 100 = 40.$I think the office worker making$\$30,000$ is in the 40th percentile. and I'm not sure what this ranking indicates. I thank you for any helpful reply and or different calculation.

Hi Kenneth,

Your calculations are correct but rather than saying

Add the number of salaries. Total: 5

you should say

Count the number of salaries. Total: 5

and rather than saying

Add the smallest number of salaries less than $\$30,000.$There are two. you should say Count the number of salaries less than$\$30,000.$ There are two.

The fact that $\$30,000$is at the$40^{th}$percentile means that$40 \%$of the employees earn less than$\$30,000.$

Harley

Math Central is supported by the University of Regina and The Pacific Institute for the Mathematical Sciences.