7th Grade Math

Multi-Part

Lesson (^3) Predictions
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Multi-Part
Lesson 3
Get ConnectED
GLE 0706.5.3
Formulate questions and
design studies to collect data
about a characteristic shared
by two populations, or
different characteristics
within one population.
GLE 0706.5.5 Understand
and apply basic concepts of
probability.
468 Probability and Predictions
Main Idea
Predict actions of a
larger group by using
a sample.
Vocabulary
survey
population
sample
Use Data to Predict
TELEVISION The circle
graph shows the results of a
survey in which children ages 8
to 12 were asked whether they
have a television in their
bedroom.

1. Can you tell how many were
   surveyed? Explain.


2. Describe how you could use
   the graph to predict how
   many students in your
   school have a television in
   their bedroom.

A survey is designed to collect data about a specific group of people,

called the population. A smaller group called a sample must be

chosen. A sample is used to represent a population. If a survey is

conducted at random, or without preference, you can assume that

the survey represents the population. In this lesson, you will use the

results of randomly conducted surveys to make predictions about

the population.

TELEVISION Refer to the graphic above. Predict how many out of

1,725 students would not have a television in their bedroom.

You can use the percent equation and the survey results to predict

what part p of the 1,725 students have no TV in their bedroom.

part = percent · whole

p = 0.54 · 1,725 Survey results: 54%

p = 931.5 Multiply.

About 932 students do not have a television in their bedroom.

a. TELEVISION Refer to the same graphic. Predict how many out of

1,370 students have a television in their bedroom.

54%

No

Television

in Bedroom

46%

Television

in Bedroom

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