Constant of Proportionality Problems

If Justin can type 408 words in 4 minutes, Let the number of minutes be x and the number of words typed be y. What is the constant of proportionality?

Alycia earned $20.40 in 3 hours. Let the number of hours be x and the money earned be y. What is the constant of proportionality?

• $7 per hour

• $6 per hour

• $6.80 per hour

• $17.40 per hour

In the equation y = 14x, what is the constant of proportionality?

• x

• 14

• y

Find the constant proportionality of 624 calories in 3 servings.

• 1,872 calories per serving

• 208 calories per serving

• 624 calories per serving

• 621 calories per serving

You spend $40 on 5 pounds of concrete. What is the unit rate in dollars per pound?

• $8 per pound

• $35 per pound

• $5 per pound

• 0.125 pounds per dollar

What makes a graph proportional?

• A straight line (linear) that goes through the origin

• Linear (straight line), that does NOT go through the origin.

One kilometer is 1000 meters. Complete the tables. What is the interpretation of the constant of proportionality in each case?

meters	kilometers
1,000	?
250	?
12	?
1	?

The constant of proportionality tells us that:

kilometers	meters
1	1,000
5	?
20	?
0.3	?

The constant of proportionality tells us that: What is the relationship between the two constants of proportionality?

Which statement matches the graph?

• Taylor can write 6 words per minute

• Taylor can write 25 words per minute

• Taylor can write 50 words per minute

• Taylor can write 150 words per minute

Which of the following statements is TRUE about the graph? Choose all that apply.

• The point (2, 8) shows that 8 pounds of cheese cost$2.00.

• The point (1.5, 6) shows the cost is $6.00 for 1.5pounds of cheese.

• The point (0.75, 3) shows that 0.75 pound of cheesecosts $3.00.

• The point (0.25, 1) shows the cost is $0.25 for 1pound of cheese.

• The point (0, 0) shows the cost is $0.00 for 0 pounds of cheese