Average Annual Salary of a Cosmetologist. As of 2008 the median salary for a cosmetologist in the United States was $11.13, which includes tips and commission. The lower 10th percentile earned on average $7.47 hourly, while the upper 90th percentile earned a median salary of $20.41 hourly.verage Annual Salary of a Cosmetologist. As of 2008 the median salary for a cosmetologist in the United States was $11.13, which includes tips and commission. The lower 10th percentile earned on average $7.47 hourly, while the upper 90th percentile earned a median salary of $20.41 hourly.
The median is the ((n + 1)/2)th item, where n is the number of values. For example, for the list {1, 2, 5, 7, 8}, we have n = 5, so the median is the ((5 + 1)/2)th item.
to calculate Q1 and Q3, you must first find Q2 - the median. count from wither end of the sample until you find the sole middle number, or find the average of the 2 middle numbers. then, complete the same process to the left of Q2 for Q1, and also on the right for Q3. the IQR is just Q3 - Q1. 27 people found this useful.