Basic College Mathematics (ALEKS)
Section 9 – 1
Chapter Nine - Introduction to Statistics
Tables, Bar Graphs, Pictographs, and Line Graphs
INTRODUCTION TO DATA AND TABLES
Data – information
Table – rows and columns – individual entries are cells
Statistics – math that involves collecting, organizing, and analyzing data.
1.
Andrew
2.
Katrina
3.
Fran – Alicia = 37 – 19 = 18 deaths
4.
1
௄௔௧௥௜௡௔
ி௥௔௡
=
଼ଵ.ଶ
ହ.଼
= 14 times
Chapter 9
Basic College Mathematics (ALEKS)
Chapter Nine - Introduction to Statistics
BAR GRAPHS
2
Chapter 9
Basic College Mathematics (ALEKS)
Chapter Nine - Introduction to Statistics
PICTOGRAPHS
3
Chapter 9
Basic College Mathematics (ALEKS)
Chapter Nine - Introduction to Statistics
LINE GRAPHS
4
Chapter 9
Basic College Mathematics (ALEKS)
Section 9 – 2
Chapter Nine - Introduction to Statistics
Frequency Distribution and Histograms
FREQUENCY DISTRIBUTION is a table displaying the number of
values that fall within categories called CLASS INTERVALS.
5
Chapter 9
Basic College Mathematics (ALEKS)
Chapter Nine - Introduction to Statistics
HISTROGRAM – is a special bar graph that illustrates the data in a
Distribution Frequency.
6
Chapter 9
Basic College Mathematics (ALEKS)
Section 9 – 3
Chapter Nine - Introduction to Statistics
CIRCLE GRAPHS
CIRCLE GRAPHS – or Pie Charts, where slice of the pie, or SECTOR,
shows how whole amount is divided into parts.
7
Chapter 9
Basic College Mathematics (ALEKS)
Chapter Nine - Introduction to Statistics
CIRCLE GRAPHS AND PERCENTS
Section 9 – 4
Mean, Median, and Mode
Mean – (average) sum of the values divided the number of values.
8
Chapter 9
Basic College Mathematics (ALEKS)
MEAN =
Chapter Nine - Introduction to Statistics
sum of the values
number of values
Housing prices: $108,000;
$149,000; $164,000; $118,000;
$144,000; a) find the mean?
b) new house $1,300,000 is built.
Find the mean of all six?
a)
108K+149K+164K+118K+144K =
$683,000
$଺଼ଷ,଴଴଴
Mean =
= $136,600
ହ
b)
683000+1300000=1,983,000
ଵଽ଼ଷ଴଴଴
= $330,500
Mean =
଺
MEDIAN – is the middle number in an ordered list of numbers.
Procedure:
1) First, arrange the numbers ordered from least to greatest.
2) If number in list is ODD, median is middle number.
3) If EVEN, median is the average of middle two numbers.
a) Find the median of the first five 108, 118, 144, 149, 164
housing costs:
Median = $144,000
b) add the sixth house:
108, 118, 144, 149, 164, (1,300)
ଵସସାଵସଽ
Median =
=$146,500
ଶ
MODE – is the value of values that occur most often. BIMODAL – is
when TWO values occur most often. If more than two values occur
most often, they say there is no mode.
Find the mode of the rainfall
amounts:
4.5, 3.0, 3.2, 3.5, 5.1, 6.8, 4.3, 4.5,
5.6, 5.3, 4.5, 3.8
9
3.0, 3.2, 3.5, 3.8, 4.3, 4.5, 4.5, 4.5,
5.1, 5.3, 5.6, 6.8
4.5 (there are 3 of them)
Chapter 9
Basic College Mathematics (ALEKS)
Chapter Nine - Introduction to Statistics
Find mode of baby weights:
7.2, 8.1, 6.9, 9.3, 8.3, 7.7, 7.9, 6.4,
7.5
6.4, 6.9, 7.2, 7.5, 7.7, 7.9, 8.1, 8.3,
9.3
NO Mode
GRADE POINT AVERAGE (GPA) – A WEIGHTED MEAN
Grade
A
B
C
D
F
Points
4
3
2
1
0
GRADE POINTS = CLASS CREDITS (UNITS) TIMES GRADE
Course
Intermediate Algebra
Theater
Music
History
Grade
B
C
A
D
Units
4
1
3
5
Grade Points
4x3 = 12
1x2 = 2
3x4 = 12
5x1 = 5
Total Grade Points = 12 + 2 + 12 + 5 = 31
Total Units = 4 + 1 + 3 + 5 = 13
GPA =
்௢௧௔௟ ீ௥௔ௗ௘ ௉௢௜௡௧௦
்௢௧௔௟ ௎௡௜௧௦
=
ଷଵ
ଵଷ
Compare to straight average:
10
= 2.38462 = 2.38
஺ା஻ା஼ା஽
ସ
=
ସାଷାଶାଵ
ସ
=
ଵ଴
ସ
= 2.5
Chapter 9