1. PERCENT OF INCREASE OR DECREASE
STANDARDS 1.3, 1.6
PERCENT OF INCREASE OR DECREASE
Problem 1
Problem 2
Problems 3
Problem 4
Problem 5
Problems 6
Problems 7
END SHOW
PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

2. GRADE 7: Number Sense
1.3 Convert fractions to decimals and percents and use these representations in estimations, computations and applications.
1.3 Convertir fracciones a decimales y porcentajes y usar estas representaciones en estimaciones, cálculos y aplicaciones.
1.6 Calculate the percentage of increase and decrease of a quantity.
1.6 Calcular el porcentaje de incremento y decremento de una cantidad.
PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

3. CHANGE % of CHANGE = ORIGINAL
Original Price is $.40 and New Price is $.60. Find the percent of increase or decrease:
% of CHANGE =
CHANGE
ORIGINAL
ORIGINAL PRICE=$.40
NEW PRICE=$.60
What is the percent of change between the original price and the new?
STANDARDS 1.3, 1.6
PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

4. CHANGE % of CHANGE = ORIGINAL
Original Price is $.40 and New Price is $.60. Find the percent of increase or decrease:
CHANGE
% of CHANGE =
ORIGINAL
What is the ratio that compares the change in price with the original price?
.60 –.40
% of CHANGE =
.40 5
.20
.20
.40 = - 20
.40
= .5
$.60 – $.40
CHANGE IN PRICE
$.40
ORIGINAL PRICE
Now convert it to PERCENT:
(.5)
(100%)
= 50 %
=$.20
So, the price was INCREASED 50%
STANDARDS 1.3, 1.6
PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

5. CHANGE % of CHANGE = ORIGINAL
Original Price is $.66 and New Price is $.22. Find the percent of increase or decrease:
% of CHANGE =
CHANGE
ORIGINAL
ORIGINAL PRICE=$.66
NEW PRICE=$.22
What is the percent of change between the original price and the new?
STANDARDS 1.3, 1.6
PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

6. CHANGE % of CHANGE = ORIGINAL .
Original Price is $.66 and New Price is $.22. Find the percent of increase or decrease:
CHANGE
% of CHANGE = 6 6
ORIGINAL
.44
.66
=0.66 44
6600 - 39 6 44
What is the ratio that compares the change in price with the original price? - 39 6 44
.22 –.66
% of CHANGE =
.66
-.44 =
.66 . 22 = 44
6600
$.22 – $.66
CHANGE IN PRICE = 2
300
Now convert it to PERCENT:
-0.66 2
300 %
= -66 2 3
(100%)
= -.44 or
-66.7%
So, the price was DECREASED approximately 66.7%
STANDARDS 1.3, 1.6
PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

7. CHANGE % of CHANGE = ORIGINAL
Original Price is $.39 and New Price is $.59. Find the percent of increase or decrease:
% of CHANGE =
CHANGE
ORIGINAL
ORIGINAL PRICE=$.39
NEW PRICE=$.59
What is the percent of change between the original price and the new?
STANDARDS 1.3, 1.6
PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

8. CHANGE % of CHANGE = ORIGINAL
Original Price is $.39 and New Price is $.59. Find the percent of increase or decrease:
CHANGE
% of CHANGE =
ORIGINAL
What is the ratio that compares the change in price with the original price?
.59 –.39
% of CHANGE =
.39 5 1
.20
.20
.39 =
=0.51 11
3900 - 19 5
.39 5
=0.51 11
3900
$.59 – $.39
CHANGE IN PRICE - 39
$.39
ORIGINAL PRICE 11
Now convert it to PERCENT:
0.51 11
3900 %
= 51 11 39
(100%)
=$.20 or
51.3%
So, the price was INCREASED approximately 51.3%
STANDARDS 1.3, 1.6
PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

9. CHANGE % of CHANGE = ORIGINAL . .
Original Price is $120 and New Price is $140. Find the percent of increase or decrease:
% of CHANGE =
CHANGE
ORIGINAL
ORIGINAL PRICE=$120
Change in price =
$140
– $120
NEW PRICE=$140
= $20
What is the ratio that compares the change in price with the original price?
140 – 120
% of CHANGE = 1 6
120 . 2 1 6
= 0.16 2
300 . 2
=0.16 4
600 20 - 6 = 4
120 - 36 1 6 = 4
= 0.16 2
300
So, the price was INCREASED approximately 16.7%
Convert to percent:
0.16 2
300 %
= 16 2 3
(100%) or
16.7%
STANDARDS 1.3, 1.6
PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

10. CHANGE % of CHANGE = ORIGINAL .
The number of deer in the zoo changed from 60 t0 20. What was the percent of change?
% of CHANGE =
CHANGE
ORIGINAL
ORIGINAL NUMBER= 60
Change in number = 20
– 60
NEW NUMBER= 20
= 40
What is the ratio that compares the change in deer before and after?
20 – 60
% of CHANGE = 6 6 60 2 3 . 20
=0.66 2
300
- 40 - 18 = 2 60 - 18 2 3
= - 2
= -.66 2
300
So, the number of deer was DECREASED approximately 66.7%
Convert to percent:
-.66 2
300 %
= -66 2 3
(100%) or
-66.7%
STANDARDS 1.3, 1.6
PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

11. CHANGE % of CHANGE = ORIGINAL .
The number of horses in a ranch changed from 80 to 200. What was the percent of change?
% of CHANGE =
CHANGE
ORIGINAL
ORIGINAL NUMBER= 80
Change in number =
200
– 80
NEW NUMBER= 200
= 120
What is the ratio that compares the change in horses before and after?
200 – 80
% of CHANGE = 80 1 5 . 40
120 3 2 = 2 80 1 3 2 = 10
=1.5
So, the number of horses was INCREASED approximately 150%
Now convert to PERCENT:
(1.5)
(100%)
= 150 %
STANDARDS 1.3, 1.6
PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

12. CHANGE % of CHANGE = ORIGINAL .
In a High School there were 150 juniors in 1979, now in 2004 there are 450. What was the percent of change?
% of CHANGE =
CHANGE
ORIGINAL
Juniors in 1979 = 150
Change in number =
450
– 150
Juniors in 2004 = 450
= 300
What is the ratio that compares the change in juniors from one year to the other?
450 – 150
% of CHANGE =
150 .
150
300 =
150 2 1 =
= 2
So, the number of juniors was INCREASED 200%
Now convert to PERCENT:
(2)
(100%)
= 200 %
STANDARDS 1.3, 1.6
PRESENTATION CREATED BY SIMON PEREZ. All rights reserved