Allison’s Math Test Scores
Test
Scores
1
89
2
98
3
85
4
94
5
?
The table shows Allison’s scores on four tests. What
score does she need on the 5th test to have an overall
mean score of 92?
1. Add up the points for the first 4 test scores.
89 + 98 + 85 + 94 =
366
2.
Find out how many points it would take to get a 92
average.
92 x 5 =
460
2.
Subtract to find the points needed on the 5th test.
460-366 =
94
 A set of data collected to answer a statistical question
has a distribution which can be described by its center,
spread, and overall shape.
 CENTER - A measure of center summarizes all of the
values of a data set with a single number (mean,
median, mode)
 SPREAD - Describes how spread out or varied the data
is (range)
 OVERALL SHAPE – Skewed left, skewed right, normal
distribution, uniform distribution, bimodal
distribution
 Mean – also called the average, fair share or balance point
of a set of data – it can be found using a leveling strategy or
by finding the sum of the data divided by the number of
pieces of data.
 Median – the middle number in a set of data ordered from
smallest to largest. If the data set has an odd number of
elements, the median is the single middle value. If the data
set has an even number of elements, the median is the
average of the two middle values.
 Mode – the number(s) that occur(s) most often (there can
be more than one mode in a data set)
 Range – the difference between the greatest and least
values of the set
 Mean Absolute Deviation- the absolute value of
each data point from the mean of the data set
Hey diddle diddle
The median’s in the middle;
You add and divide for the mean.
The mode is the one that appears the most
And the range is the difference between.
Find the mean number of
points scored.
Find the median number of
points scored.
What do the values of the mean
and median tell you about
the overall shape or
distribution of the data?
Player
Points
Ethan
16
Collin
9
Nathan
10
Mason
4
Tyler
12
Aaron
8
Cole
2
 Each of the 20 students in Mr. Anderson’s class timed
how long it took them to solve a puzzle. Their times
(in minutes) are listed below:
Student
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
2
0
Time (in
minutes
3
5
4
6
4
8
5
4
9
5
3
4
7
5
8
6
3
6
5
7
 Display the data using a line plot.
 Find the mean and median of the data. Does it
surprise you that the values of the mean and median
are not equal? Explain why or why not.
http://www.illustrativemathematics.org/illustrations/877
Bimodal Distribution
Normal Distribution
Uniform Distribution
Skewed Right
Skewed Left