Page 206 - Math Course 1 (Book 1)

Percent of Increase and Decrease

Step 1 •Burbank
Subtract to f nd the amount of change. 104, 114 – 93, 643 10, 471
25,500 – 7500 = 18,000 =
new tuition – original tuition 93, 643 93, 643

Step 1 = 0.1118 or 11.2%
Write a ratio that compares the amount of change
to the original tuition. Express the ratio as a
percent. •Monterey
amount of change Eliminate this choice because the population
Percent of Change = decreased.
original tuition

18,000 •San Jose
= Substitution.
7500 904, 522 – 782, 248 122, 274
782, 248 = 782, 248

Write the decimal as = 2.4% or 240%
a percent. = 0.1563 or 15.6%

The percent of change is 240%. Burbank had the least percent of
Answer In this case, the percent of Answer increase in population from
change is a percent of increase. 1990 to 2004. The answer is B.

Standardized Test Example
Your Turn!

Example Find Percent of Increase

TEXTBOOKS
Refer to the table shown. Which city had the least In 1990, the price of a textbook was $38. In 2000,
percent of increase in population from 1990 to the price of the same textbook was $81. Find the
2000?
percent of change.

City 1990 2004 A. 47%
B. 53%
Anaheim 266, 406 333, 776 C. 113%
D. 213%
Burbank 93, 643 104, 114
Answer
Monterey 31, 954 29, 669
San Jose 782, 248 904, 522 Find Percent of Increase

A. Anaheim B. Burbank The table shows test scores on the f rst two math
C. Monterey D. San Jose tests of the semester for four students. Which
student had the greatest percent of increase
Read the Test Item from test 1 to test 2?
Percent of increase tells how much the population
has increased in relation to 1990. Student Test Score Test 2 Score
Holly 84 91
Solve the Test Item Ben 93 89
Use a ratio to f nd each percent of increase. Then
compare the percents. Sally 65 79
Max 73 98
•Anaheim A. Holly B. Ben
333, 776 – 266, 406 67, 370 C. Sally D. Max
266, 406 = 266, 406
Answer
= 0.2529 or 25.3%
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