Chapter 15 Lesson 3 Finding Outcomes Pages all

Cornell Notes – Chap. 15 Lesson 3 Main Ideas/Cues: Disjoint events Details: Events that have no outcomes in common. Example: When rolling a number cube, the events getting an odd number and getting a 4 are disjoint events.

Cornell Notes – Chap. 15 Lesson 3 Main Ideas/Cues: Overlapping events Details: Events that have one or more outcomes in common. Example: When rolling a number cube, the events getting a number less than 3 and getting an even number are overlapping events because they have the outcome 2 in common.

Cornell Notes – Chap. 15 Lesson 3 Main Ideas/Cues: Complementary events Details: Two disjoint events such that one or the other of the events must occur. Example: When rolling a number cube, the events getting an odd number and getting an even number are complementary events.

Cornell Notes – Chap. 15 Lesson 3

Problem #1 First Step: Write the Problem 1. Tell whether the events involving the spinner are disjoint or overlapping. Event R: Spin a number divisible by 4. Event S: Spin a prime number

Problem #1 Second Step: List the numbers for each event. 1. Event R: 4 and 8 Event S: 2, 3, and 7 Spin a number divisible by 4 Spin a prime number

Problem #1 Third Step: Are any outcomes in common? 1. Event R: 4 and 8 Event S: 2, 3, and 7 Disjoint; No outcomes are in common, a prime number is not divisible by any number other than 1 and itself.

Problem #2 First Step: Write the Problem 2. Malcolm has 2 green tiles, 4 yellow tiles, and 3 blue tiles in a bag. He chooses 1 tile out of the bag without looking. What is the probability that the tile is green or blue?

Problem #2 Second Step: Rewrite using the Probability formula. 2. P(green or blue) = P(green) + P(blue) P( ) Number of green tiles + Number of blue tiles Total number of tiles Total number of tiles

Problem #2 Third Step: Add the fractions. 2. P(green or blue) = P(green) + P(blue) = Answer

Problem #3 First Step: Write the Problem 3. On a subway, 30% of the riders have briefcases. What is the probability that a randomly chosen rider does not have a briefcase? About how many riders out of 350 would not have a briefcase?

Problem #3 Second Step: Change the percent to a decimal and subtract from P(has a briefcase) = 1 – P(does not have a briefcase) 1 – 0.3 = 0.7 ; 70% do not have a briefcase What is the decimal for 30%? How many do not have a briefcase? Answer to the first question!

Problem #3 Third Step: Now find 70% of 350. Write the percent equation and replace the variables with the known numbers 3. a = 70% 350 a = a = riders out of 350 would not have a briefcase. a = p% b Answer to the second question! Change the percent to a decimal Answer

Cornell Notes Summary Include the following statement and answer in your Cornell Notes Summary. How do you find the probability that either event A or event B will occur if they are disjoint events? You can find the probability that either event A or event B will occur if they are disjoint events by ____________.