Question

In the past 6 days, Carmela’s travel time to work has varied: 34 minutes, 20 minutes, 27 minutes, 21 minutes, 29 minutes, and 19 minutes. The work shown is her calculation of the mean absolute deviation of the time traveled. Which step contains the first error Carmela made?

Answer 1

Answer: Step 2, because she did not find the absolute value of all the differences.

Answer 2

The step that contains the first error Carmela made is, 'she did not find the absolute values of the differences.'

Solution-

In calculation of mean absolute deviation, we find each distance from the mean, because it is the absolute value of the deviation (how far from the mean).

`\text{Mean Deviation}=(\sum \left | x-\mu \right |)/(N)`

The steps to calculate mean absolute deviation,

1. Calculate the mean of all values
2. Calculate the distance of each value from that mean (subtract the mean from each value and ignore minus signs)
3. Then calculate the mean of those distances.

Therefore, because she did not find the absolute values of the differences, is her first error.