Warm Up

Find the mean of the following:12, 3, 5, 9, 215, 7271, 35, 106, 24320, 30, 10, 501, 2, 3

Agenda

Warm Up (10) Notes (20) EQ Task “Sad to Mad” (30) Practice Problems (20) Ticket out the Door Homework

Notes

Standard: MA1D4. Students will explore variability of data by determining the mean absolute deviation (the averages of the absolute values of the deviations).

Key VocabularyMean-averageMode-number that occurs the mostMedian-the middle numberSummationMEAN ABSOLUTE DEVIATION (MAD)

Summation

Summation – add the series or sequence of numbers.

Symbol:

Example:

nn1

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Mean Absolute Deviation (MAD)

The (MAD) is used as a way to determine the variability of data.Variability means the variance (spread) in

different things such as test scores, results, or other data.

The formula to find the mean absolute Deviation:

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Essential Question (EQ)

How can I quantify the variability of a distribution?

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Task

“Sad to Mad”

Practice--Find the MAD

Find the MAD of 1, 1, 4, 7, 12 Step 1: Find the mean ( )

(1+1+4+7+12)÷5= 5 Step 2: Sum the absolute deviations

from the mean ( )|1-5|+|1-5|+|4-5|+|7-5|+|12-5|

=4+4+1+2+7=18 Step 3: Divide by the number of data

points ( )18/5=3.6

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Ticket out the Door

Describe how you would find the MAD of a set of numbers.