Constant Rate of Change Word Problems

A plumber charges $25 for a service call plus $50 per hour of service. Write an equation that can be used to find y, the total cost, if x represents the number of hours of service?

• y=75x

• y=2x+25

• y=25x+50

• y=50x+25

A holiday meal cost $12.50 a person plus a delivery fee of $30. Which equation represents the amount a holiday meal costs(y), including delivery, for x people?

• y = 12.50 + 30x

• y = 30 + 12.50x

• y = 12.50 + 30

• 12.50x = 30

Analyze the point (3, 27). What does the point represent? 

• The point (3,27) represents 27 shirts for $3. 

• The point (3,27) represents $27 for 3 shirts. 

• 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

Find the rate of change.

• -2 minutes per gallon

• -20 minutes per gallon

• -2 gallons per minute

• -20 gallons per minute

Mr. Z is starting his own car club, there is a $30 join up fee and a $5 monthly fee. What is the rate of change?

• 30

• 5

Who has the greater rate of change?

• Smith has the greater rate of change.

• Harmon has the greater rate of change.

• Macey has the greater rate of change.

• They have the same rate of change

Suppose that the water level of a river is 34 feet and that it is receding at a rate of 0.5 foot per day.

The slope (m) is ____.

A bus company took a tour bus on the ferry when there were 30 people aboard. The ferry charged the bus company $180.

The following week, the bus had 50 people on board and the ferry charged them $220.

What is the equation (y=mx+b) that represents this situation?

A plumber charges $25 for a service call plus $50 per hour of service.

Write an equation to represent the situation. Use x and y as your variables.