8-4 Percent of Change

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8-4 Percent of Change

• (Page 350-353)

Indicator? N8 Develop and analyze algorithms for
computing with percent and demonstrate fluency in
use.
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• A percent of change is a ratio that compares the
  change in quantity to the original amount.
• If the original quantity increased, it is a
  percent of increase.
• percent of increase
• If the original quantity decreased, it is a
  percent of decrease.
• percent of decrease

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To find the percent of change

• Use the correct equation.
• percent of increase
• percent of decrease
• Which ever equation you choose, your amount of
  change will ALWAYS be positive!

New amount - original amount
Original amount - new amount
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Example 1 (percent increase)

• Last year a sweater sold for 56. This year the
  same sweater sells for 60. Find the percent of
  change in the cost of the sweater. Round to the
  nearest whole percent if necessary.

New amount - original amount
percent of increase
Simplify
percent of increase
0.071428571
Change to a
7
Write a sentence.
The cost of the sweater increased 7 since last
year.
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Example 2 (percent decrease)

• On the first day of school this year, 435
  students reported to TVMS. Last year on the first
  day, 460 students attended. Find the percent of
  change for the first day attendance. Round to the
  
• nearest whole percent.

Original amount - new amount
percent of decrease
percent of decrease
Simplify
0.054347826
Change to a
5
Write a sentence.
The first day attendance at TVMS decreased 5
since last year.
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• Homework
• 8-4
• P. 352-353 20-41