Question

The ratio of the number of cups of blue paint to the number of cups of red paint that Lara mixed to make a shade of purple paint is 3.1.
Part A: Write a sentence to describe the number of cups of blue paint that Lara mixed with each cup of red paint (4 points)

Part B: How many cups of red paint should Lara add to each cup of blue paint to make the shade of purple? Explain your reasoning (4 points)

Part C: I Lara purchased 6 cups of blue paint for $48, what is the unit price per cup of blue paint? (2 points)

Answer 1

Answer:

Part A

The number of cups of blue paint that Lara mixed with each cup of red paint is 3 cups of blue paint

Part B

1/3 cup of red paint is added to 1 cup of blue paint

Part C

The unit price per cup of blue paint is $8 per cup of blue paint

Step-by-step explanation:

The ratio of the number of cups of blue paint to the number of cups of red paint that Lara mixed to make a shade of purple paint is 3: 1

Part A: Write a sentence to describe the number of cups of blue paint that Lara mixed with each cup of red paint (4 points)

The ratio is

Blue paint : Red paint

= 3 : 1

Hence,

The number of cups of blue paint that Lara mixed with each cup of red paint is 3 cups of blue paint

Part B: How many cups of red paint should Lara add to each cup of blue paint to make the shade of purple? Explain your reasoning (4 points)

From Part A , we know that

3 cups of blue paint = 1 cup of red paint

1 cup of blue paint = y

Cross Multiply

3 × y = 1 × 1

y = 1/3

Hence, 1/3 cup of red paint is added to 1 cup of blue paint

Part C: I Lara purchased 6 cups of blue paint for $48, what is the unit price per cup of blue paint? (2 points)

6 cups of blue paint = $48

1 cup of blue paint = x

6 × x = $48 × 1

x = $48/6

x = $8