1. Percents, Proportionality and Similarity
Warm - up
Dazzling Decimals
Power point
Raging Ratios
Guided Practice
Every Day Unit Rates

2. Dazzling Decimals
Warm Up
1. Ms. Davis is making candied cashews to give away as gifts. How many 0.75 pound bags can be made from 4.5 pounds of cashews?
4.5 ÷ 0.75 = 6 bags
2. The Thompson family purchased 8.8 gallons of gasoline for$ How much did they pay per gallon?
$18.04 ÷ 8.8 = $2.05 per gallon

3. Ratio and Proportions
Equal Ratios
Unit Rates
Ratios

4. Never heard of ratios before?
If you’ve done fractions you have done ratios, because ratios are fractions.
Look at this problem.
Your softball team has won 7 games and lost 3 games . What is the ratio of games won to games lost?
What are you being asked to do?
Write a ratio/fraction for number of games won to number of games lost.
A ratio can be written as a fraction because a ratio is a fraction. We are comparing wins to losses, so the first number in the ratio should be the number of wins and the second number is the number of losses.
Discuss with students that they are to write a fraction comparing the number of games the won and those lost. Students discuss which number is the numerator and the denominator. Students may want to convert to a mixed number so discuss with them that because you want to see the comparison of the wins to losses it must be kept in fraction form.
The ratio is games won
_7 games = 7_
games lost
3 games 3
What is the ratio of games won to games played? Can you write this ratio?
The ratio is games won = _7 games won = 7
games played games played

5. A ratio is the comparison of two or more numbers by division.
Ratios
A ratio is the comparison of two or more numbers by division.
There are 3 ways to write a ratio.
Ratios can be written with-
as a fraction
a colon (:)
the word to

6. With a partner, compare 3 games lost and 7 games won using the three representations: to, colon(:) fraction
part-to-part
won to lost
7 to 3
7 : 3 7 3
3 to 7
3 : 7 3 7
lost to won
part-to-total
7 to 10
7 :10 7 10
won to games played
3 to 10
3 : 10 3 10
lost to games played
total-to-part
10 to 7
10 : 7 10 7
games played to games won
10 to 3
10 : 3 10 3
games played to games loss

7. A unit rate is a rate with a denominator of 1.
Snicker Bars are on sale 4 for a $ How much is each candy bar?
$0.25 is the price of each candy bar.
This called unit rate.
A unit rate is a special ratio that compares quantities in different units.
A unit rate is a rate with a denominator of 1.
cost
candy 4 4
$1.00
$0.25 1 =
This means $0.25 per bar, each bar, or for 1 bar

8. Everyday Unit Rates Guided Practice
1. The Dart Rail train travels 300 miles in 60 minutes.
What is the rate per minute?
A regular size box of breakfast cereal weighs 12 oz. and costs $ The family size box of the same breakfast cereal weighs 20 oz. and costs $4.00.
a. Which box would you buy?
b. Explain why.

9. Everyday Unit Rates Guided Practice
1. The Dart Rail train travels 300 miles in 60 minutes.
What is the rate per minute?
miles
minutes
300mi
60min 60
5 mi
1 min =
5 miles in 1 minute
5 miles each minute
5 miles per minute

10. Everyday Unit Rates
2. A regular size box of breakfast cereal weighs 12 oz. And costs $ The family size box of the same breakfast cereal weighs 20 oz. And costs $ Which box would you buy? Explain why.
12 oz. box
20 oz. box
cost
oz.
$3.00
12oz. 12
12. =
$0.25 per oz.
cost
oz.
$4.00
20oz. 20 =
$0.20 per oz.
It costs more but is less per ounce. You get more cereal for the money buying the family size box.