Below is a dot plot of the number of snapchats sent per day in Mr. Elkins' class. Part A: Which value is smaller, the mean or the median?

Question
Scatterplots
asked 2021-02-13
Below is a dot plot of the number of snapchats sent per day in Mr. Elkins' class. Part A: Which value is smaller, the mean or the median?

Answers (1)

2021-02-14

The mean is equal to the sum of the values divided by the number of values. The mean is then:
mean=(19+20+2(21)+3(22)+4(24)+27)/12 =270/12 =22.5
The median is the middle value when there is an odd number of values and the average of the two middle values when there is an even number of values. There are 12 values so the median is the average of the 6th and 7th values. The 6th and 7th values are both 22 which means their average must also be 22.
Since 22 is smaller than 22.5, then the median is the smaller value.

 
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