Answer: 6
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Step-by-step explanation:
First we need to find the mean.
Add up the values to get 20+13+3 = 33+3 = 36
Then divide that sum by 3 because we're dealing with three values
We get 36/3 = 12.
The mean is 12.
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From here we subtract the mean (12) from each data value of the set {20,13,3}
So we get these differences
- 20-12 = 8
- 13-12 = 1
- 3-12 = -9
Here's where the term "absolute" comes in. More specifically, we'll use absolute value. This is to ensure we don't get a negative value when we subtract. So whatever results above are negative, we just flip to the positive version when we apply absolute value.
- |20-12| = 8
- |13-12| = 1
- |3-12| = 9 .... this value is now positive
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The set of results we got were {8, 1, 9}
Let's compute the mean of this new set
Add up the values: 8+1+9 = 9+9 = 18
Divide by three: 18/3 = 6
The mean absolute deviation is 6.