Name Class Date

Practice

Conditional Probability

Use the table to find each probability.

Guitars
Acoustic / Electric
Tan / 78 / 42
Black / 34 / 56
Blue / 12 / 16
1. P(black | acoustic) / 2. P(tan | electric) / 3. P(blue | electric)
4. P(acoustic | tan) / 5. P(tan | acoustic) / 6. P(electric | blue)

The following table shows national employment statistics. Use the table to find
each probability.

7. P(male | professional) / 8. P(laborer | female) / 9. P(female | sales)
10. P(professional | female) / 11. P(sales | male) / 12. P(male | laborer)

Prentice Hall Foundations Algebra 2 • Teaching Resources

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Name Class Date

Practice (continued)

Conditional Probability

Use the Conditional Probability Formula and the table below to answer the
following questions.

Students’ Reading Preferences
Comic Books / Novels
Middle School / 128 / 32
High School / 86 / 98

13. What is the probability that a student prefers comic books, given that the
student is in high school?

P(B | A)

P(high school and comic books) P(high school)
P(comic books | high school)

14. What is the probability that a student prefers novels, given that the student is
in middle school?

15. Writing Tony wants to know the probability that his classmate is left-handed,
given that she is female. Should he use conditional probability? Explain why
or why not.

Use a tree diagram to solve the following problem.

16. A car insurance company compiled the following information from a recent
survey.

·  75% of drivers carefully follow the speed limit.

·  Of the drivers who carefully follow the speed limit, 80% have never had an
accident.

·  Of the drivers who do not carefully follow the speed limit, 65% have never
had an accident.

What is the probability that a driver does not carefully follow the speed limit
and has never had an accident?

Prentice Hall Foundations Algebra 2 • Teaching Resources

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