Construct Functions From Word Problems

Bob's Plumbing charges $15 per hour plus a service fee of $40 for coming out to your house. Which equation models this situation?

• y = 15x + 40

• y = 40x + 15

• y = 15x

• y = 15x - 40

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

Eddie's Electric charges $90 per hour plus a $50 traveling fee. Which equation models this scenario?

• y = -50x + 90

• y = 90x + 50

• y = -90 - 50x

• y = 50 - 90x

Ace Telecommunications charges $0.12 per minute of phone use plus a monthly service fee of $8.00 for it phone service. Which equation can be used to find c, the total cost for one month when m, minutes are used?

• c = 0.12m + 8m

• c = 8m + 0.12m

• c = 0.12m + 8

• c = 0.20m

Thomas got a speeding ticket. The officer said he had to pay $10 for each mile(m) per hour he was going over the speed limit plus $115 in court cost. Which equation models the total cost of Thomas' fine?

• c = 125m

• c = 10m + 115

• c = 115m + 10

• c = 10m - 115

Daniel is paid $10 per week for selling newspaper subscriptions. He is also paid $3.50 for each new customer(x) that signs up for the subscription. Which equation represents the amount(y) Daniel earns in a week?

• y = 10 + 3.50x

• y = 10 + x

• y = 3.50x

• y = 3.50x

Ace Communications charges $15.00 per month plus $0.20 per minute of airtime usage. If Juanita uses m minutes of airtime, which equation can be used to determine her monthly cell phone bill(c)?

• c = 15 + m + 0.20

• c = 15 + 0.20m

• c = 15(0.20m)

• c = 0.20 + 15m

A fitness club opens with 80 members. Each month the membership increases by 15 members. Which equation represents the relationship between the number of months the club has been opened, x, and the total fitness club membership, y?

• y=15x
• y=15x+80
• y=x+15
• y=80x+15

Which of the following situations could be descried by the equation y= -25x + 120

• There are 120 people in the football stadium, and 25 more are entering each hour.
• A plumber charges $25 for a house call and $120 per hour.
• A teacher has 120 students. Her third period has 25 students
• There are 120 gallons of water in a tank. It releases water at a rate of 25 gallons per minute

Bob has $150 in his savings account and saves $40 per month.  Which equation represents the amount Bob has in his account after x months?

• y = 150 + 40
• y = 40x + 150
• y = 150x + 40