Tuesday, December 6th
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Transcript of Tuesday, December 6th
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