Function Rules Word Problems

Rufus collected 100 pounds of aluminum cans to recycle. He plans to collect an additional 25 pounds each week. Write the equation for the total pounds, P, of aluminum cans after w weeks. How long will it take Rufus to collect 400 pounds of cans?

• P = 100w + 25

• 12

• 20

• P = 25w + 100

A taxicab charges $4.25 for a ride and $1.50 per mile. Write a rule for describing the total rate r as a function of the total miles m. What is the taxi rate for 12 miles?

• 22.25

• r = 4.25m + 1.50

• 52.50

• r = 1.50m + 4.25

A plumber charges a service fee of $40 plus $25 per hour for labor.
Write a function rule for the total cost of hiring the plumber for a job that takes x hours.
How much would it cost to hire the plumber for a job that takes 4 hours?

• y = 40 + 25x
  $140

• y = 40x + 25
  $185

• y = 40 + 25x 
  $185

• y = 40x + 25 
  $140

The school cafeteria has 285 cartons of milk in stock. Each day, a total of 60 cartons are sold. Which function rule best represents this situation?

• y = 285x + 60 

• y = 285x - 60

• y = 285 - 60x

• y = 285 + 60x

The temperature (T) increases by 5 degrees Fahrenheit every hour. Write a function rule to represent the temperature after 'h' hours if the initial temperature is 70 degrees Fahrenheit.

• T=70 * 5h

• T=70 + 5h

• T=70 - 5h

• T=70 + 5h

The cost of renting a bicycle is $10 per hour. Write a function rule to represent the total cost (C) of renting the bicycle for 'h' hours.

• C = 5h

• C = 20h

• C = 10h

• C = 10/h

The temperature (T) decreases by 2 degrees Celsius every hour. Write a function rule to represent the temperature after 'h' hours if the initial temperature is 25 degrees Celsius.

• T=25 - 2

• T=25 - 2h

• T=25 - h

• T=25 + 2h

A car rental company charges a flat fee of $50 plus $20 per day for renting a car. Write a function rule to represent the total cost (C) of renting the car for 'd' days.

• C = 50 * 20d

• C = 50 - 20d

• C = 50 + 20d

• C = 50d + 20

A company charges $30 per month for a gym membership. Write a function rule to represent the total cost (C) of the gym membership for 'm' months.

• C = 30m

• C = 30m^2

• C = 30/m

• C = 30 + m

A phone plan charges a flat fee of $20 plus $0.10 per minute for calls. Write a function rule to represent the total cost (C) of making 'm' minutes of calls.

• C = 20 * 0.10m

• C = 20 + 0.10m

• C = 20 + 0.10m + 5

• C = 20 - 0.10m