Bell Work/Cronnelly Write your answers as a fraction and percent.

1) Ken is apple bobbing. The tub contains 8 red, 6 green, and 4 yellow apples. If Ken closes his eyes and bites into the first apple he can reach, what color apple is he least like to get?_______________________

What is the probability the apple will be green?________________________

2) A bag contains 4 blue marbles, 3 red marbles, and 1 orange marble. If a marble is taken from the bag at random, what is the probability the marble will be red? _____________

What is the probability the apple will be blue or orange?________________________

Solve:

3) 4) 5) 6)

Bell Work/Cronnelly

Write your answers as a fraction and percent.1) Ken is apple bobbing. The tub contains 8 red, 6 green, and 4 yellow apples. If

Ken closes his eyes and bites into the first apple he can reach, what color apple is he least like to get?_______________________

What is the probability the apple will be green?________________________

2) A bag contains 4 blue marbles, 3 red marbles, and 1 orange marble. If a marble is taken from the bag at random, what is the probability the marble will be red? _____________

What is the probability the apple will be blue or orange?________________________

Solve:

3) 4) 5) 6)

Yellow6/18; 1/3; 33 1/3%

3/8; 37.5 %

5/8

3) 4.64 4) 32.882 5) 2.2225 6) 5.355

Homework ANSWERS1-103:

a) Yes, 10/25=40/100 = 2/5 . Sample reasoning: the shape can be rearranged and divided into groups of 5 squares, each with 2 shaded; both the numerator and denominator of the fraction can be multiplied by .b)

1-104. 12. 12 ÷ 2 = 6, 6 – 4 = 2

1-105: a) 1/4 , 25%b) 18/50, 36%c) 1-1/2 , 150%

1-106: a) 4/8 or 1/2 b) b) 31/20 or 1 11/20c) 16/35

1-107: a) 25b) 45

c) 30

So far in this section, you have worked with probabilities involving one specific desired outcome.  Now you will investigate probabilities of compound events.  Compound events are events with combinations of outcomes.  In today’s lesson, you will find the probability that either one of the events or the other event occurs.  (In Chapter 5, you will consider the probability that both one event and another event occur.) 

Think about these questions as you work with your study team:

• How is this probability related to the probability of a single event?

• Either what event or what other event are we interested in?• Does our answer make sense?

1-119. Thomas helps around the house by doing one chore after school.  Each day, Thomas and his aunt use the spinner at right to decide which chore he will do. Here is what Thomas knows:

-The sections on the spinner for “rake leaves” and “do laundry” are the same size.-The sections for “clean bathroom” and “vacuum” are equal in size and together make up half the spinner.

a. What is the probability that Thomas will spin “do laundry”?  

b. Thomas hates to clean the bathroom.  When he spins the spinner, what is the probability that it will not point to “clean bathroom”?  Explain how you found your answer. 

1-120. Thomas’s aunt hopes that he will either spin “clean bedroom” or “rake leaves” today.

a. What is P(clean bedroom)?  What is P(rake leaves)? 

b. Spinning either chore in part (a) would make Thomas’s aunt happy.  With your study team, discuss the questions below and record your team’s answers.  Be sure to justify your conclusions.

~What is the probability that he will spin either one of the chores?

 

~How can you write the two outcomes as a single probability? 

1-122. Ms. Lawson lets her students borrow pens and pencils on days when they have a quiz.  She has a paper bag containing hundreds of wooden pencils, mechanical pencils, and blue pens. 

Stuart forgot his pencil, and it is quiz day!  Ms. Lawson tells him that one out of every three students who reaches into the bag pulls out a wooden pencil.  Two out of every five students pull out a mechanical pencil.  The rest of the students pull out a blue pen.

Felicia was trying to find the probability that she would pull either a wooden pencil or a mechanical pencil out of Ms. Lawson’s bag from problem 1-121.  “I think I need to combine the probability that I will get a wooden pencil with the probability that I will get a mechanical pencil,” she said.  She set up this expression and drew a picture:

a. Felicia wondered if she could add the parts.  Is the sum  ? Why or why not?  

b. Discuss with your team how Felicia could change the way she writes each fraction so that she can add them easily.  Be ready to explain your reasoning.  Then, find the sum. 

1-123. Steve shuffles a standard deck of 52 playing cards and starts to turn them over one at a time.  The first three cards he turns over are an ace, a 4, and a jack. Explore using the 1-123 Student e-Tool  to access all of the cards in a standard deck.

a. How many cards are left in the deck?  

b. How many of the remaining cards are aces?  

c. What is the probability that the fourth card will be an ace? 

d. Instead of getting an ace, he gets a 2 as the fourth card.  The fifth card is a 5.  What is the probability that the next card will be a king?

Practice

1. - = 4. + =

2. + = 5. - =

3. - = 6. - =