Lesson 7-4 Example 4

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Lesson 7-4 Example 4
7-4
Solve. The ratio of brown-eyed students to the
total number of students in a sixth-grade class
is 24 out of 40. What is the probability if one
student is picked by the teacher without looking
that the student will not have brown eyes?
Understand Read the problem. Write what you
know. Out of 40 students, 24 have brown eyes.
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Lesson 7-4 Example 4
7-4
Plan Pick a strategy. One strategy is to use
logical reasoning.
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Lesson 7-4 Example 4
7-4
Solve Write the ratio of brown-eyed students to
the total students.
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Lesson 7-4 Example 4
7-4
The probability of choosing a student who does
not have brown eyes is the same as the difference
of the ratio of the entire class and the ratio of
brown-eyed students.
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Lesson 7-4 Example 4
7-4
Check Check your answer. The sum of the
probability that an event occurs and probability
that the event does not occur is 1. Is the sum
of your probabilities equal to one? Explain.