3-4 Constant of Proportionality

Is it proportional? If so, what is the constant of proportionality?

 $y=0.5x-2$  

• Yes; 0.5

• Yes; -2

• Yes; 2

• No

Is it proportional? If so, what is the constant of proportionality?

 $y=1,000x$  

• Yes; 1,000

• Yes; -1,000

• Yes; 1

• No

Is it proportional? If so, what is the constant of proportionality?

 $y=x+1$  

• Yes; 1

• Yes; -1

• Yes; x

• No

A half dozen cupcakes cost $15. What constant of proportionality relates the number of cupcakes and the total cost? Write an equation that represents this relationship.

• y=15x

• y=6x

• y=2.50x

• y=12x-15

The manager of a concession stand estimates that she needs 3 hot dogs for every 5 people who attend a baseball game. If 1,200 attend the game, how many hot dogs should the manager order?

• 200 hot dogs

• 380 hot dogs

• 640 hot dogs

• 720 hot dogs

What is the constant of proportionality in the equation

 $y=5x$  

• 5

• -5

• y

• x

What is the constant of proportionality in the equation

 $y=-0.41x$  

• 0.41

• -0.41

• y

• x

The equation P=3s represents the perimeter P of an equilateral triangle with side length s. Is there a proportional relationship between the perimeter and the side length of an equilateral triangle? Explain.

• Yes; The equation P=3s is in the form y=kx, so the relationship is proportional.

• Yes; The perimeter and side length are multiples of each other.

• Yes; An equilateral triangle is proportional.

• No

In a chemical compound, there are 3 parts zinc for every 16 parts copper, by mass. A piece of the compound contains 320 grams of copper. Write and solve an equation to determine the amount of zinc in the chemical compound.

• $y=0.1875x;\ \ 80$ grams

• $y=0.1875x;\ \ 60$ grams

• $y=20x;\ \ 60\$ grams

• $y=5.3x;\ 1,706$ grams

The weight of 3 eggs is 120g. Assuming the three eggs are all the same weight, find the constant of proportionality.

• 3

• 120

• 40

• 12