1. Day 11 Percent Change.notebook February 25, 2013
AIM: Percent Increase/Decrease
Do Now
Evaluate the following problems using the
order of operations.
a.) -1
3
- 2
5 ( -2
3
)
+2 b.) -3 8 - 13 ÷
-2
3
1

2. Day 11 Percent Change.notebook February 25, 2013
100%: 4 + 1(4) = 8 DOUBLE
200%: 4 + 2(4) = 12 TRIPLE
2

3. Day 11 Percent Change.notebook February 25, 2013
Anticipatory Set
1.) The price of gas is $3.80 a gallon. Next month the
price increases 7%. What is the new price?
2.) The month after the 7% increase, that price
decreases by 7%. What is the cost of a gallon of gas
now?
3.) What do notice about the final answer compared to
the original cost?
3

4. Day 11 Percent Change.notebook February 25, 2013
Population of New York City
The population of New York City was 7.3 million people
in 1990. The population was up to 8.2 million by 2010.
What is the percent of increase between 1990 to 2010?
Follow-up Question: How did that compare to the percent of
increase in the amount of NYPD officers between 1990 to 2010?
4

5. Day 11 Percent Change.notebook February 25, 2013
The following is an excerpt from Newsday 2/15/12
The WHO estimates polio cases have
dramatically plummeted- by about 99 percent- since
the 1988 launch of the Global Polio Eradication
Initiative.
Through the ongoing eradication initiative, only
222 confirmed cases were caused by the wild type
of the virus in 2012, according to the WHO.
QUESTION: How many polio cases were there in
1988?
5

6. Day 11 Percent Change.notebook February 25, 2013
Practice:
1.) John used to weigh 270 pounds and now
weighs 216. What is the percent decrease
in the weight of John?
2.) The price of a gallon of milk is $3.50,
but could have gone up by 130% if Congress
did not pass a farm subsidy last December.
What would the price have been after the
increase?
3.) The price of Gold has decreased by 8%
over the past six months. If the price was
$1800 an ounce then, what is the price
now?
6

7. Day 11 Percent Change.notebook February 25, 2013
Before You Leave
1.) Create a percent increase or decrease
word problem with your partner.
2.) Trade with another partnership and
solve their problem.
7

8. Day 11 Percent Change.notebook February 25, 2013
Homework
1.) Finish Class Notes
2.) Cumulative Review Sheet #15
due Tuesday 2/26
8

9. Day 11 Percent Change.notebook February 25, 2013
9