Ratios
Proportions
Real World Ratios
Percents, Fractions, Decimals
Find the Percent
100
Out of 20 friends, 7 wear Nike shoes. The rest wear Reebok. What is the ratio of students who wear Nike shoes to those who wear Reebok?
20 - 7 = 13 Reebok Shoes
Nike: Reebok
7 : 13
This is a PART TO PART ratio.
100
Do the ratios form a proportion? Prove it!
¿Las razones forman una proporción? ¡Demuéstralo!
Yes! Double it!
100
A recipe calls for 1/2 cup of milk. How much milk would you need if you were DOUBLING the recipe?
Una receta requiere 1/2 taza de leche. ¿Cuánta leche necesitarías si duplicaras la receta?
MULTIPLY BY 2!
1 cup milk
100
Change the following to decimals:
Convierta lo siguiente a decimales:
A) 1/2
B) 1/5
C) 1/4
D) 1/10
These are decimals you should memorize!
A) 1/2 = 0.5
B) 1/5 = 0.2
C) 1/4 = 0.25
D) 1/10 = 0.1
100
Larissa read 45 pages of her 87 page book, what percentage did she read?
Larissa leyó 45 páginas de su libro de 87 páginas, ¿qué porcentaje leyó?
What is 50%?
35/70 x 100 = 50%
200
In a certain math class, 12 students wore a jacket to class. 15 students did not wear a jacket. What is the ratio of students who didn't wear a jacket to the total number of students in the math class?
12 + 15 = total # students = 27
No Jacket : Total Students
15 : 27
This is a PART TO WHOLE ratio.
200
Do the ratios form a proportion? Prove it!
No!
200
A recipe calls for 2/3 cup of sugar. How much sugar would you need if you were HALVING the recipe?
Una receta lleva 2/3 de taza de azúcar. ¿Cuánta azúcar necesitarías si redujeras la receta a la mitad?
*MULTIPLY BY 1/2
(2/3) x (1/2) = 2/6 = 1/3 cup sugar
*OR DIVIDE BY 2!
200
Change 2/9 to a decimal.
Change 2/9 to a decimal.
2/9 = 0.2222.....
Answer:
0bar .2
200
JC completed 4 of the 16 slides. What percentage did he complete?
JC completó 4 de las 16 diapositivas. ¿Qué porcentaje completó?
What is 25%?
300
What is the ratio of Additional Cost to the number of Pizza Toppings?
Cost : Toppings
$2 : 1 topping
300
What is one ratio equivalent to 1:2?
¿Cuál es una proporción equivalente a 1:2?
2:4, 3:6, 4:8............
300
A 24 oz jar of pickles cost $2.49. What is the unit rate?
A 24 oz jar of pickles cost $2.49. What is the unit rate?
$2.49 / 24 oz = 0.10 = 10 cents per ounce
300
Change 3.5 to a percent.
Convierte 3.5 a un porcentaje.
3.5 x 100 = 350%
MULTIPLY BY 100!
Or, just move the decimal point two places to the RIGHT!
300
Carlos worked 6 out of 20 days. What percentage of the days did he work?
Carlos trabajó 6 de los 20 días. ¿Qué porcentaje de los días trabajó?
What is 30%?
6/20 x 100 = 30%
400
Find the missing numbers in the ratio table:
400
What are two ratios equivalent to 3 to 5?
6:10, 6 to 10, 15:25............
400
A 9.9 oz bag of Blue Heat Takis cost $3.89. What is the unit rate?
Una bolsa de 9,9 onzas de Takis Blue Heat cuesta 3,89 dólares. ¿Cuál es el precio unitario?
$3.89 / 9.9 oz = 0.39 = 39 cents per ounce
400
Change 15% to a decimal.
Convierte 15% a decimal.
15/100 = 0.15
DIVIDE BY 100!
Or, just move the decimal point (You can't see it, but it's technically behind the 15!) two places to the LEFT!
400
Isadora knew 4 out of the 5 songs, what percentage of songs did she know?
Isadora conocía 4 de las 5 canciones, ¿qué porcentaje de los canciones conocía?
What is 80%?
4/5 x 100 =80%
500
What does the information in the ratio table mean?
Find the missing values in the ratio table.
This table is comparing the amount of time a person spends reading verses watching TV.
For every 1 minute spent reading, this person spends 4 minutes watching TV.
500
What are two ratios equivalent to 6:8?
ANSWERS VARY: 3:4, 12:16, 24:32...
DOUBLE BONUS IF YOU HAVE 9:12
500
Which is the better deal?
A) 18 candy bars for $21.49
B) 12 candy bars for $14.16
¿Cuál es la mejor oferta?
A) 18 barras de chocolate por $21.49
B) 12 barras de chocolate por $14.16
A) unit rate = $21.49 / 18 = $1.19 per candy bar
B) unit rate = $14.16 / 12 = $1.18 per candy bar
OPTION B IS THE BETTER DEAL!
Use Desmos to help with the division!
500
Change 25% to a fraction.
Convierte 25% a fracción.
25% = 25/100 = 1/4
500
How do you write 45 out of 30 as a percentage?
¿Cómo se escribe 45 de 30 como porcentaje?
What is 150%?
45/30 x 100=150%