Function Notation & Describe Rules

The function C(m) = 1.45m + 3.50 represents the cost of a taxi for m miles.
What does C(7) represent?

• A cost of $7 to ride the taxi
• The cost to ride 7 miles
• The minimum distance to ride a taxi
• The minimum cost of a taxi

The function h(t) represents the height in inches of a plant after t weeks. What does the notation h(4) = 5 mean?

• After 5 week the plant is 4 inches tall
• The plant grows at a rate of 5/4 inch per week
• After 4 weeks the plant is 5 inches tall
• The plant grows at a rate of 1 inch per week

Ms. Brackemyer is collecting pencils.  The function p(x)=5x+12 tells us the total amount of pencils Ms. Brackemyer has after collecting for x number of days.  What is the meaning of p(8)=52?

• Ms. Brackemyer starts with 8 pencils and ends with 52.
• After 8 days, Ms. Brackemyer has 52 pencils.
• Ms. Brackemyer starts with 52 pencils and gets 4 more every day.
• Every day, Ms. Brackemyer gets 4 new pencils until she has 52.

Bob's Plumbing charges $25 per hour plus a service fee of $40 for coming out to your house. Which function models this situation?

• C(x) = 25x + 40

• C(x) = 40x + 25

• C(x) = 25x

• C(x) = 25x - 40

Speedy Boat Rental charges a $15 deposit fee plus $2 for each hour of use to rent a paddle boat. Write a function to represent this situation.

• R(x)= 2x + 15

• R(x)= 15y + 2

• R(x) = 15x+ 2

The Roaming Cell Phone Company charges $15.00 per month plus $0.20 per minute of airtime usage.  If Juanita uses x minutes of airtime, what is a function that can be used to determine her monthly cell phone bill (C)?

• C(x) = 0.20x + 15

• C(x) =15 (0.20x)

• C(x) = 15 + x + 0.20

• C(x) = 0.20 + 15x

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

• M(x) = 30 + 12.5x 

• M(x)= 12.5 + 30

• M(x)= 12.5 + 30x