Tuesday, December 6th

• Please come get new warm ups! • Did you write down your

homework?

WARM UPWrite each percent or decimal as a

percent1. 6/25 2. .3456

Corny Joke of the Day

What do you call a cow who can’t

give milk?

An “udder” failure!

Do you Remember?□When you make a decimal a percent

you can really move the decimal _______ places to the ___________.

□When you make a fraction a percent you want to make an equivalent fraction that has a denominator of _____________________.

Homework Answers

FindingPercents

Of a Number

The Meat of it

□A percent proportion compares part of a quantity to the whole quantity, this is called the base.

□The percent is always written as a fraction with a denominator of 100. “Per” means out of, and “cent” refers to 100.

□Ratio Part (is) and whole (of)

Setting it up

( )( ) 100

part is percentwhole of

Three ways you will see a problem

Type Example Proportion

1. Find the

PercentWhat percent of 6 is 3?

 2. Find

the Part What number is 50% of 6? 

3. Find the

Whole3 is 50% of what number?

 

36 100

x

50

6 100x

3 50

100x

Fill in your table!!!

Caution

You will have to solve proportions to work

with percents!

Proportion Review

Cross Multiply and Divide

75 9x

Part 1

Finding the percent

What percent of 6 is 3?

( )( ) 100

part is percentwhole of

36 100

percent

12 100

percent 100÷ 2=50

You Try #1What percent of 5 is 2?

( )( ) 100

part is percentwhole of

You Try #2What percent of 12 is 7?

( )( ) 100

part is percentwhole of

Part 2

Finding the Part

What number is 50% of 6

( )( ) 100

part is percentwhole of

50

6 100Part

1

6 2part 6 ÷ 2=3

You Try #1

What number is 25% of 24

( )( ) 100

part is percentwhole of

You Try #2What number is 10% of 32

( )( ) 100

part is percentwhole of

Part 3

Finding the Whole

What number is 3 is 50% of what number?

( )( ) 100

part is percentwhole of

3 50

100whole

3 1

2whole6 ÷ 1=6

You Try #1What number is 11 25% of?

( )( ) 100

part is percentwhole of

You Try #2What number is 15 30% of

( )( ) 100

part is percentwhole of

Real Life Application

There are 480 students in Sara’s school. If 70% of

the students participate in the fundraising program,

how many students participate in the

fundraising program?

Now solve: s 480

___ 70 100

___ =

100 • s = 70 • 480 100s = 33,600100s 100

____ 33,600 100

_____ = s = 336

Let s represent the number of students who participate in the fundraising program.The cross products are equal.s is multiplied by 100.Divide both sides of the equation by 100 to undo multiplication.

Since 336 is close to your estimate of 375, 336 is a reasonable answer.336 students participate in the fundraising program.

Answer

Tanner is 25% of the way through his exercises. If he has exercised for 20

minutes so far, how much longer does he have to work out?

is of

__ % 100

___ =

100 • 20 = 25 • m

25% of the exercises are completed, so 20 minutes is 25% of the total time needed.

The cross products are equal.

20 m

__ 25 100

___ = Set up a proportion. The “of” part is what you have been asked to find.

Answer