Page 460 - Algebra 1

SOLUTION
Probability can be used to determine the number of people. The events are mutually exclusive.
P(A or B) = P(A) + P(B) P(employed or ≥ 75) = P(employed) + P(≥75)
=291+ 29 __
510 510
= 32 _
51
Briceson can expect 32 out of 51 people to be employed or to be at least 75 years old. Multiply the probability by the 125 people.
_ 125 · 32
_51
= 4000 51
≈ 78
Briceson can expect to call about 78 people who are either employed
or 75 or older.
Application: Digital Music
Natalia has music from a variety of different artists on her MP3 player. There are 26 rock artists, 18 pop artists, 19 country artists, 10 alternative artists, and 7 crossover artists. The music by the crossover artists Natalia chose is on the pop and country charts. If Natalia’s music player randomly selects the next artist, what is the probability that the artist will be singing a pop or country song?
SOLUTION
Find the total number of outcomes.
26 + 18 + 19 + 10 + 7 = 80
The events are inclusive events because the crossover artists are considered to be both country and pop artists.
P(A or B) = P(A) + P(B) - P(A and B)
P(pop or country) = P(pop) + P(country) - P(pop and country)
=25+26- 7 ___
80 80 80
= _1 1 20
There is an _11 chance that the music player will choose a pop or 20
country song next.
Math Reasoning
Verify Why is 51 rounded to the nearest whole number in Example 3?
4000 _
Example
4
Lesson 68 445