Do Now 4/20/10Do Now 4/20/10

Take out HW from last night.Take out HW from last night.Text p. 792, #1-8 allText p. 792, #1-8 allText p. 793, #1-6 allText p. 793, #1-6 all

Copy HW in your planner.Copy HW in your planner.Text p. 355, #8-24 evensText p. 355, #8-24 evens

Skills Review HandbookSkills Review Handbook“Angles and Measurement”“Angles and Measurement”

There are 4 types of angles:There are 4 types of angles:

Acute angleAcute angle – has a measure of less than 90 – has a measure of less than 90°°

Right angleRight angle – has a measure of exactly 90° – has a measure of exactly 90°

Obtuse angleObtuse angle – has a measure of more than 90 – has a measure of more than 90°°

Straight angleStraight angle – has a measure of exactly 180– has a measure of exactly 180°°

Skills Review HandbookSkills Review Handbook“Angles and Measurement”“Angles and Measurement”

Use a protractor to measure an angle.Use a protractor to measure an angle.

1) 381) 38°° 2) 134°2) 134° 3) 84°3) 84° 4) 52°4) 52° 5) 5)

6) 6)

7) 7)

8) 8)

Skills Review HandbookSkills Review Handbook“Units of Measurement”“Units of Measurement”

1) 921) 92°; obtuse°; obtuse 2) 180°; straight angle2) 180°; straight angle 3) 61°; acute3) 61°; acute 4) 157°; obtuse4) 157°; obtuse 5) 126°; obtuse5) 126°; obtuse 6) 135°; obtuse6) 135°; obtuse

Text p. 793, #1-6 allText p. 792, #1-8 all

55°

168°

90°

77°

Chapter 7 “Percents”Chapter 7 “Percents”

Section 7.1 “Percents and Fractions”Section 7.1 “Percents and Fractions”

Section 7.2 “Percents and Proportions”Section 7.2 “Percents and Proportions”

Section 7.3 “Percents and Decimals”Section 7.3 “Percents and Decimals”

Section 7.4 “The Percent Equation”Section 7.4 “The Percent Equation”

Section 7.5 “Percent of Change”Section 7.5 “Percent of Change”

Section 7.6 “Percent Applications”Section 7.6 “Percent Applications”

Section 7.7 “Simple and Compound Interest”Section 7.7 “Simple and Compound Interest”

ObjectiveObjective SWBAT find a percent of change in a quantitySWBAT find a percent of change in a quantity

The percent of change of a quantity is given by:The percent of change of a quantity is given by:

The percent is a The percent is a PERCENT of INCREASE PERCENT of INCREASE if the if the quantity increased and it is a quantity increased and it is a PERCENT of PERCENT of DECREASE DECREASE if the quantity decreased. if the quantity decreased.

Amount of changeAmount of change Original amountOriginal amount

Section 7.5 “Percent of Change”Section 7.5 “Percent of Change”

Percent of changePercent of change indicates how much a quantity indicates how much a quantity increases or decreases with respect to the original increases or decreases with respect to the original amount.amount.

x 100x 100

The percent of change of a quantity is given by: The percent of change of a quantity is given by:

Find the percent of increase or decrease Find the percent of increase or decrease (round to the nearest tenth of (round to the nearest tenth of

a %).a %). Before: 30 Before: 30 After: 45 After: 45 Before: 115 Before: 115 After: 46 After: 46

Before: 116 After: 146 Before: 116 After: 146

50% increase 50% increase

60% decrease 60% decrease

25.9% 25.9% increase increase

Amount of changeAmount of change Original amountOriginal amount

x 100x 100

The percent of change of a quantity is given by: The percent of change of a quantity is given by:

From 2006-2007 to 2007-2008 the From 2006-2007 to 2007-2008 the enrollment increased by 200, thereforeenrollment increased by 200, thereforeour answer is a percent of increase.our answer is a percent of increase.

actual changeactual changeoriginal amountoriginal amount

200200 11001100

≈ ≈0.1818180.181818

≈ ≈18% increase18% increase

The enrollment of Howell Middle School South in The enrollment of Howell Middle School South in 2006-2007 was 1100 students. In the year 2007-2008 2006-2007 was 1100 students. In the year 2007-2008 the enrollment was 1300 students.the enrollment was 1300 students.

What is the percent of increase or decrease between What is the percent of increase or decrease between the two years? the two years?

Percent of increase =

2007-2008: 13002007-2008: 1300 2006-2007: – 2006-2007: – 11001100 change: 200. change: 200.

Amount of changeAmount of change Original amountOriginal amount

x 100x 100

The percent of change of a quantity is given by: The percent of change of a quantity is given by:

From 1990 to 1991 the number of computersFrom 1990 to 1991 the number of computersused increased by 0.2 million or 200,000. used increased by 0.2 million or 200,000.

amount of changeamount of changeoriginal amountoriginal amount

0.2 million0.2 million 2 million2 million

=0.1=0.1

=10% =10% increaseincrease

There were 2.2 million computers used in public schools in 1991There were 2.2 million computers used in public schools in 1991and 2 million in 1990. Find the percent of increase.and 2 million in 1990. Find the percent of increase.

Percent of increase = Percent of increase =

1991:1991: 2.2 million 2.2 million 1990: 1990: - 2.0 million- 2.0 million change: 0.2 million or 200,000change: 0.2 million or 200,000. .

Amount of changeAmount of change Original amountOriginal amount

x 100x 100

Who is Watching MTV???Who is Watching MTV???

48

33

28

25 25

28

31

0

10

20

30

40

50

60

1985 1987 1989 1991 1993 1995 1997

Year

Pe

op

le o

f W

atc

hin

g (

in m

illio

ns

)

People Watching

Find the percent of change Find the percent of change from 1985 to 1987. from 1985 to 1987.

Find the percent of change Find the percent of change from 1993 to 1997? from 1993 to 1997?

48

3348

original

change3125.0

48

15

Decrease Decrease 31.25%31.25%

25

2531

original

change24.0

25

6

Increase 24%Increase 24%

Using a Percent of ChangeUsing a Percent of Change

There were about 198,000 spectators at There were about 198,000 spectators at the NCAA Final Four in 1995. The number of the NCAA Final Four in 1995. The number of spectators increased by about 12% from 1995 to spectators increased by about 12% from 1995 to 2002. About how many spectators were there in 2002. About how many spectators were there in 2002? 2002?

Spectators in 2002 = Spectators in 1995 + Amount of increase

= 198,000 + (12% · 198,000)

= 198,000 + 23,760

= 221,760

Using a Percent of ChangeUsing a Percent of Change

In 1983, the average price of CD was In 1983, the average price of CD was $21.50. By 2000, the average price had $21.50. By 2000, the average price had decreased by 34.8%. What was the average decreased by 34.8%. What was the average price of a CD in 2000? price of a CD in 2000?

Price in 2000 = Price in 1983 x Percent of change

= $21.50 x (100% – 34.8%)

= $21.50 x 65.2%

= $14.018 = $14.02

HomeworkHomeworkText p. 355, #8-24 evensText p. 355, #8-24 evens

2424

HomeworkHomework

Why Did the Sea Monster Eat 27 Ships Carrying Potatoes?Why Did the Sea Monster Eat 27 Ships Carrying Potatoes?

NOBODY CAN EAT JUST … ONE POTATO SHIPNOBODY CAN EAT JUST … ONE POTATO SHIP

What Magic Trick Did Poof the Great Perform When He Visited Helsinki?What Magic Trick Did Poof the Great Perform When He Visited Helsinki?

HE VANISHED INTO FINN AIRHE VANISHED INTO FINN AIR