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Percent of Change. How much did a gallon of milk cost in the 1950’s?. What happens when you keep sharpening your pencil?. What if you get a raise in your allowance?. Percent of Change:. Compares the amount of change to the ORIGINAL amount!. Percent of Increase:.
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How much did a gallon of milk cost in the 1950’s? What happens when you keep sharpening your pencil? What if you get a raise in your allowance?
Percent of Change: • Compares the amount of change to the ORIGINAL amount!
Percent of Increase: • An increase from the ORIGINAL amount Ex) The cost of milk in the 1950’s compared to today’s cost.
Percent of Decrease: • A decrease from the ORIGINAL amount Ex) What happens to your pencil when you keep sharpening it?
Amount of Change = • The difference between the ORIGINAL amount and the NEW amount. Life expectancy in 1900 was 45 years old; Life expectancy in 2012 is 78 years old. What is the amount of change? 78 – 45 = 33
Percent of Change Proportion: SUBTRACT!!! Amount of Change % --------------------------- = ------------------------- 100 ORIGINAL Amount 78 – 45 = 33
Steps for Finding Percent of Change: • Determine whether the amount is INCREASING or DECREASING from the ORIGINAL amount.
Steps for Finding Percent of Change: 2. Find the amount of CHANGE. SUBTRACT!!! 3. Set-up the Percent Proportion. % Amount of Change --------------------------- = ------------------------- 100 Original Amount
Example 1: An 8 ft. tree grows to be 10 ft. tall in the last year. What is the tree’s percent of change? Increase or Decrease? 25 2 ft % Amount of Change --------------------------- = ------------------------- 100 8 ft Original Amount
Example 2: A pair of jeans was originally priced at $40, but is on sale for $36. What is the percent of change? Increase or Decrease? $4 10 % Amount of Change --------------------------- = ------------------------- 100 $40 Original Amount