Page 195 - Math Course 3 (Book 2)

Sampling and Bias

Systematic random sample Your Turn!
Definition Examples
In a systematic random Every 2 minutes, an item Classify a Random Sample
sample, the items are is pulled off the
selected according to a assembly line or At an automobile factory, every tenth item is
specified time or item checked for quality controls. Identify the sam-
interval. Every twentieth item is ple and suggest a population from which it was
pulled off the assembly selected.
line.
A. The sample is every tenth item. The population
is all of the products that are manufactured in
the factory.
Let’s Begin
B. The sample is all products that are
manufactured in the factory. The population is
every tenth item.
Classify a Random Sample
C. The sample is a car. The population is all cars.
Example D. The sample is unbiased. The population is all
cars.

RETAIL
Each day, a department store chain selects one Answer
male and one female shopper randomly from each
of their 57 stores and asks them survey questions At an automobile factory, every tenth item is
about their shopping habits. checked for quality controls. Classify the sample
as simple, stratified or systematic.
A. simple random sample
B. stratified random sample
C. systematic random sample
D. none of the above

Answer

Identify the sample and suggest a population from
which it was selected.

The sample is 57 male and 57
female shoppers each day. The
Answer
population is shoppers in the
chain’s stores.

Classify the sample as
simple, stratified, or systematic.

The population is divided into similar,
nonoverlapping groups.

Answer This is a stratified random sample.

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