Transcript Math Review: line plots , bar graphs, mean, median, mode

Math Review: line plots, bar
graphs, mean, median, mode,
range
V. Martinez
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What is a line plot?
 A line plot displays data along a
number line.
 Each x represents one number in the
data.
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Outlier
 A number in a data set that is very
different from the other numbers.
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Here, x’s = houses with pets
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Average Number of Emails
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x
x
x
x
x
x
x___x___x_____x__________
1
2
3 4 5 6
Emails sent today
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What is the average number of emails sent today?
Remember to find the average : ADD and Divide
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
What is the range?
What is the mode?
What is the median?
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What is the outlier here?
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What is the Median?
text pg. 226
 The median is the middle number
when the data are listed in order.
 The number of raisins in our boxes:
 10, 26, 26, 27, 30, 32, 32, 32, 34
x
30 is the median.

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What is the mode?
 The mode is the number or numbers
that occur most often in the data.
10, 26, 26, 27, 30, 32, 32, 32, 34
The mode is 32.
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What is the range?
 The range is the difference between
the greatest and the least number in
the data.
 10, 26, 26, 27, 30, 32, 32, 32, 34
 The greatest number is 34. The least
number is 10.
 34 – 10 = 24. The range is 24.
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What is the mean?
Pg. 404
 The mean is the average. It is found
by adding all the numbers in a set
and dividing by the number of values.
 10, 25, 20, 5, 20
 The sum is 75.
 We added 5 numbers.
 Divide 75 by 5.
 The average or mean is 15.
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Mean

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

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
The blocks
that are all
the same
height show
the average
or mean.
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Practice at this interactive website.
 http://www.bbc.co.uk/schools/ks2bit
esize/maths/activities/modemedianm
ean.shtml
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What is a bar graph?
p 208
 A bar graph is a graph using bars to
show data.
 Bar graphs can be vertical or horizontal.
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Compare and Contrast
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Parts of a bar graph
 Scale: Numbers that show the units
used on a graph are the scale.(The numbers
on the graph.)
 Interval: a number which is the
difference between two consecutive
numbers on the scale of a graph. (p. 208)

The interval is 5.
 The graph must have labels!
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Steps for creating a bar graph.
 Choose a scale.
 Draw and label the side and bottom
of the graph.
 Draw a bar on the graph for each
piece of data.
 Give the graph a title. The title shold
describe the subject of the graph.
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Make a bar graph.
 http://nces.ed.gov/nceskids/graphing
/classic/bar_pie_data.asp?ChartType
=bar
 Y axis – vertical (up and down)
 X axis – horizontal (across)
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