Solving Ratio/Rate Problems using Proportions

Solving Problems using Proportions

Resolver problemas usando proporciones

I can buy 5 cookies for $3. How much would 12 cookies cost?

Try to figure out the answer on your own.

Fill in the Blank

I can buy 5 cookies for $3. How much would 12 cookies cost?

How most people figure this out

Figure out how much 1 cookie costs by dividing. Then you multiply that answer to 12 to find the final cost.

Using a proportion is good for finding out something you don’t know from something you do know.

Proportions also keep your information organized

Steps

1. Cross Multiply (diagonal)
2. Divide by the remaining number

Pasos

Multiplicar cruzada (diagonal)

Dividir por el número restante

Steps

Multiply 4 times 15

Divide by 6

The answer is 10

Steps

Multiply 4 times 12

Divide by 3

The answer is 16

Open Ended

How do you solve a proportion?

¿Cómo se resuelve una proporción?

Multiple Choice

Solve this proportion

 $\frac{c}{8}=\frac{10}{16}$  

• 80

• 5

• 12.5

• 124

Multiple Choice

Solve the proportion.

  

 $\frac{5}{a}=\frac{30}{54}$  

• a=6

• a=9

• a=29

• a=3

Multiple Choice

Gregory bought 6 post cards for $3. How much would 10 post cards cost?

Gregory compró 6 postales por $ 3. ¿Cuánto costarían 10 tarjetas postales?

• $4.50

• $0.50

• $5.00

• $20.00

Multiple Choice

A recipe requires 2 cups of milk for every 3 cups of flour. If you use 26 cups of milk, how many cups of flour do you need?

Una receta requiere 2 tazas de leche por cada 3 tazas de harina. Si usa 26 tazas de leche, ¿cuántas tazas de harina necesita?

• 15

• 17

• 39

• 52