Page 167 - Math Course 1 (Book 2)

Probability of Simple Events

Real World Example
MO. 11 - L5b

SPORTS
Experimental Probability Miss Newman surveyed her class to see which
sports they preferred watching. 44% preferred
football, 28% basketball, 20% soccer, and 8%
tennis. Out of 560 students in the entire school,
Vocabulary A-Z how many would you expect to say they prefer
watching basketball?
Let us learn some vocabulary
The total number of students is 560. So, 560 is
the base. The percent is 28%.

experimental probability What number is 28% of 560? Write the percent
proportion. Let a represent the part.
What actually occurs when repeating a probability
experiment many times.
part a = 28 percent
number of times tails occur 11 11 base 560 100
= or
number of possible outcomes 14 +11 25
100 • a = 560 • 28 Find the cross products.
Outcome Tally Frequency 100a = 15,680 Simplify.
Heads |||| |||| |||| 14 a = 156.80 Mentally divide each
Tails |||| |||| | 11 side by 100.
The experimental probability of getting tails in this You can expect about 157
11 Answer students to say they prefer
case is or44%
25 watching basketball.

Let’s Begin
Your Turn!

Find Experimental Probability
Find Experimental Probability
BASKETBALL
Example Brian is shooting baskets with a basketball. He
makes 13 shots and misses 9 shots. Determine the
experimental probability of Brian making a shot.
A coin was tossed 40 times and heads came up
18 times. Find the experimental probability of A.
getting tails for this experiment. A.
B.
number of times tails occur 40–18 22 11 B.
= = or
number of possible outcomes 40 40 20
C.
C.
The experimental probability of
11 D.
Answer getting tails in this case is or D.
20
55%
Answer

159