Question

9 Mr. Lawrence tutored 5 students prior to the last math test. The table below shows the grades the students made. What is the mean absolute deviation of the grades rounded to the nearest hundredth? Grades 86 60 7294100 Record your answer and fill in the bubbles on your answer document. Be Sure to use the correct place value.HELPL PLSSSS!

Answer 1

To calculate the MAD (mean absolute deviation) we start by first calculating the mean.

$\begin{gathered} M=\frac{\Sigma x}{x} \\ M=\frac{\Sigma(86+60+72+94+100)}{5} \\ M=\frac{412}{5} \\ M=82.4 \end{gathered}$

The MAD takes the deviation of all the data given in absolute values and calculates the mean, as follows;

$\begin{gathered} M=\frac{\Sigma|86-82.4|+|60-82.4|+|72-82.4|+|94-82.4|+|100-82.4|}{5} \\ M=\Sigma\frac{|3.6|+|22.4|+|10.4|+|11.6|+|17.6|}{5} \\ M=\frac{65.6}{5} \\ M=13.12 \end{gathered}$

The MAD is calculated as 13.12