Page 432 - Math Smart - 7

According to the theoretical probability, Max expected the probability of the
spinner landing on the orange sector to be 2, same as the probability of landing
on the blue sector. But the experimental probability is different from the
theoretical probability.
Max decided to increase the number of trials in the experiment. His results are
recorded in the table below.

Experimental
Sector Frequency
probability
The experimental
Orange 510
1000 =0.51 probabilities: 0.51 and 0.49
are closer to the theoretical
Blue 490 490
1000 = 0.49 probability of 0.5 when the
number of trials is increased.
Total 1000 1

As the number of trials in an experiment increases, the experimental probability
becomes closer to the theoretical probability.

GROUP WORK
List all the possible outcomes for rolling a 6-sided fair die.
Calculate the theoretical probability of each outcome.

Roll the same die 100 times.
Use the table below to record your experimental data. Use tally marks to
record the number obtained each time.
Experimental probability
can be referred to as Number Tally of the number of times the Relative
Frequency
relative frequency. on dice number appeared frequency
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Spotlight
•
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;

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A biased die is also called
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a loaded die. This die ' •
•
is made to land on one

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side more often than
the other sides. This is f •
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usually done by adding
an additional weight to What are some precautions you can take to make sure the experiment is
one or more sides of the as fair as possible?
die. The probabilities
Check your experimental probabilities with another group. Do you have
of the outcomes of an
the same experimental probabilities?
experiment using a
Compare your results and discuss the difference from the theoretical
loaded die will not be
probabilities. Are your results close to the theoretical probabilities?
equal.
How can you find out if this die is a fair or biased die?
i28 UNIT 18