Grade 4 - Progress in Mathematics

Update your skills. See page 27.

Predict Probability

7-7

Use words and a fraction to write the probability

of each spinner landing on yellow.

Probability is the chance that a given event

will occur in an experiment.

Random experiments—like tossing a coin,

rolling a number cube, spinning a spinner, and

selecting an item from a set without looking—

mean you do not know what the result, or

outcome, of the experiment will be.

What is the probability of the spinner

landing on red? on blue? on white?

Tw o ways to describe

probability are in words

and as a fraction.

The spinner has 8 equalsections.

Of the equal sections, 3 are red,

3 are blue, and 2 are white.

The probability of the spinner landing on


red is 3 out of 8, or.


blue is 3 out of 8, or.


white is 2 out of 8, or.


not white is 6 out of 8, or.^68

2

8

3

8

3

8

Probability

of an event

number of favorable outcomes

number of possible outcomes

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