Date: Name:
UNIT 4. APPLICATIONS OF PROBABILITY
Lesson 2: Conditional Probability
Practice 4.2.1: Introducing Conditional Probability
Timothy rolls a pair of number cubes. Use this information to complete problems 1 and 2.
1. What is the probability that both numbers are odd if their sum is 7? What is the probability
that the sum of the numbers is 7 if both numbers are odd?
2. What is the probability that the sum is even if the product is even? What is the probability that
the product is even if the sum is even?
For problems 3 and 4, list the sample space for the given events using a tree diagram and explain what
your symbols represent
. Use conditional probability to determine if events A and B are independent;
show your work
3. Hiro rolls a number cube 3 times.
Event A: The second roll is odd.
Event B: Exactly 2 consecutive rolls are odd.
4. The Millers have 3 children.
Event A: The second oldest is a girl.
Event B: At least 2 are girls.