Page 99 - IM_Algebra1_FL Print Sample.pdf

Launch
Arrange students in groups of 2. Give students quiet think time to answer the rst question and think about the others. Ask partners to compare and discuss their answers. Follow with a whole-class discussion.
Student Task Statement
The table displays the dessert preference and dominant hand (left- or right-handed) for a sample of 300 people.
prefers cake
prefers pie
total
left-handed
10
20
30
right-handed
90
180
270
total
100
200
300
For each of the calculations, describe the interpretation of the percentage in terms of the situation.
1. 10% from 2. 67% from 3. 30% from
Student Response
Answers vary. Sample responses:
1. Out of the 100 people who prefer cake, 10% of them are left-handed.
2. Out of the 270 people who are right-handed, 67% of them prefer pie.
3. Thirty percent of everyone surveyed is both right-handed and prefers cake.
Activity Synthesis
The goal is to make sure understand that relative frequencies can be calculated using the overall total, or the totals from the rows or the columns.
Ask students who were identi ed as mentioning relative frequency, “When you said relative frequency, what did you mean?” (I meant the frequency of a particular cell in the table occurring relative to the total. For example, 10% comes from 10 left-handed people who prefer cake out of the 100 total people who prefer cake.)
Here are some questions for discussion.
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Teacher Guide
Algebra