Unit 4 Day 3
Day 3
Warm Up
Create a histogram with the following data
Interval
Frequency
5-7
4
8-10
7
11-13
7
14-16
8
Vocab
joint relative frequency: the values in each
category divided by the total number of values.
marginal relative frequency: adding the joint
relative frequencies in each row and column
conditional relative frequency: divide the joint
relative frequency by the marginal relative frequency
Standard: MGSE9-12.S.ID.5 Summarize
categorical data for two categories in two-way
frequency tables. Interpret relative frequencies
in the context of the data (joint, marginal, and
conditional relative frequencies) Recognize
possible associations and trends in the data.
Essential Question
How can you construct and interpret twoway frequency tables?
Two-Way Tables
a way to organize data that can be categorized by two
variables. Suppose you asked 20 children and adults
whether they liked broccoli. The table shows one way to
arrange the data.
The joint relative frequencies are the values in each
category divided by the total number of values, shown by
the shaded cells in the table. Each value should be divided
by 20, the total number of individuals.
The marginal
relative
frequencies are
found by adding
the joint relative
frequencies in
each row and
column.
You Try!
The table shows the
number of books
sold at a library
sale. Make a table
of the joint and
marginal relative
frequencies.
To find a conditional relative frequency , divide the
joint relative frequency by the marginal relative
frequency. Conditional relative frequencies can be used
to find conditional probabilities.
You try and be sure to ask questions, this is
what is on HW.
1. Complete the table of the joint
relative frequencies and
marginal relative frequencies.
2. If you are given that a student is
taking ballet, what is the
probability that the student is
not taking tap?
Key Terms to remember
joint relative frequency----what is inside the
table
marginal relative frequency---in the
MARGINS-each row added and each column
added
conditional relative frequency---joint relative
frequency/marginal relative frequency
HOMEWORK
On webpage: Unit 4 documents then Day 3
HW