Name: ______________________________________
Chapter 6 – Probability
Math 7A
Chapter Review
Experimental and Theoretical Probability
Probability =
favorable # of outcomes of a particular event(s)
total # of possible outcomes
Remember To Always Reduce Fractions To Lowest Terms!
1) George drew 20 cards from a deck. Four were diamonds, 7 were clubs, 3
were hearts and six were spades. Find each experimental probability.
a. P(diamonds)
_______
b. P(hearts or spades) ________
c. If George draws 20 more cards
from the deck, about how many
spades can he expect to draw?
_______
2) In practice, Sam made 19 out of 25 penalty shots. What is the
experimental probability that he will miss a penalty shot? Write
your answer as a fraction, decimal, and percent.
3) A bag contains 7 yellow, 3 green, and 4 blue marbles. One marble is chosen. Give
the probability of each event.
a. P(yellow)
_______
b. P(purple)
_______
c. P(green or blue) _______
d. P(not blue)
_______
e. P(not pink)
_______
4) A spinner is divided into five sections.
a. What is the theoretical probability of landing on green?
_______
b. The spinner is spun 45 times and
lands on blue 9 times. How does this compare to
the theoretical probability of spinning blue?
5) A recent survey was taken to ask people their favorite television station. Use the
chart below to answer the following questions:
Favorite Television Station
ABC
FOX
MTV
ESPN
WB-11
Number of Respondents
19
16
20
32
13
a) 100 people were surveyed. Theoretically, about how many should choose ESPN?
b) Based on this survey, what is the experimental probability of choosing ESPN?
Experimental Probability and Making Predictions

Find the experimental probability



Set up a proportion to figure out the prediction
Solve
Label your answer
6) When 100 children were questioned about their reading habits, 71 said they read
at bedtime. If 700 children were questioned, about how many of them would you
expect to read at bedtime?
7) The probability that a kindergartner can tie their shoes in Putnam Elementary
3
School is 5. If there are 100 kindergarteners in a school, how many would you
predict can tie their shoes?
8) In a recent survey, 9.5% of respondents stated that they do not own a computer.
Out of 4000 people, how many would you expect to own a computer?
Tree Diagrams and The Counting Principle
9) a. The employee cafeteria at a certain company offers a choice of the
following cookies with ice cream for dessert. Make a tree diagram and list
the possible dessert, you may abbreviate.
Cookie
Scoop of Ice Cream
peanut butter
vanilla
chocolate chip
strawberry
oatmeal raisin
mint chip
rocky road
b. If the cafeteria adds a sugar cookie and
peanut butter ice cream to the choices, how many possible combinations will there be?
___________
10) A family has three children.
a. List the outcomes that indicate the sex of the children. Assume that the
probability of male (M) and the probability of female (F) are each 1/2.
11) Use the counting principle to find the number of outcomes in each situation:
b. Bookcases: 20 widths, 3 heights, 5 kinds of wood
c. A pet store sells 3 breeds of dog, each breed in four colors .How many
different dogs do they sell?
Probability: Independent and Dependent events
12) A coin and a number cube are tossed. What is the probability of landing on heads
and rolling an odd number?
13) Laurel has ten scarves in a box. 4 are blue, 2 are red, 3 are green, and 1 is black.
If she draws two scarves but replaces the first before drawing the second, what is
the probability she will draw two red scarves in a row?
14) A bag contains 12 marbles: 2 blue, 4 red, 5 orange and 1 white. What is the
probability that a person will choose blue, then red, then white if the marbles are not
replaced before the next one is drawn?
15) A box contains 2 mystery books, 4 romance novels, 1 biography, and 2 science
fiction books. Bradley chooses two books from the box at the same time (without
replacement). What is the probability he will choose both mystery books?
16) There are 13 girls and 8 boys in a class. The teacher is selecting 2 students to
come to the front of the class. What is the probability the teacher will select a boy
and then a girl if the boy stays at the front of the room when the girl is called up?