L(13.2): Compare Center and Spread of Data Displayed in Box Plot

Find the Mean, Median and Mode

for the following observations :-

7 , 8 , 3 , 5 , 5 , 9 , 6 , 1 , 12 , 4

• Mean 6

  median is 5.5

  Mode is 5

• Mean 5

  median is 6

  Mode is 5

What is a dot plot?

• A dot chart or dot plot is a statistical chart consisting of data points plotted on a fairly simple scale, typically using filled in circles.

• A chart with dots.

How many kids read 3,4 and 5 books?

• 4 kids

• 5 kids

• 7 kids

• 9 kids

How many people got 4 or 5 questions?

• 7

• 9

• 8

• 10

Draw a dotplot for the data set below.

25, 25, 20, 25, 16, 20, 25, 30, 25, 31, 26, 28, 30

• 
• 

the median

of the lower half of a data set

• Lower quartile

• Upper quartile

the median

of the upper half of a data set

• Lower quartile

• Upper quartile

15, 83, 75, 12, 19, 74, 21

lower quartile:

• 15

• 75

15, 83, 75, 12, 19, 74, 21

upper quartile:

• 15

• 75

Find the lower and upper quartiles for the data

set.

• 1. Order the data from least to greatest.

  2. Find the median of the lower half – lower quartile

  3. Find the median of the upper half – upper quartile

• 1. Order the data from greatest to least .

  2. Find the median of the lower half – lower quartile

  3. Find the median of the upper half – upper quartile