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The total cost (y) at an amusement park can be modeled by y=1.5x+20 where x is the number of rides you ride. What is the price per ride?

Mathematical Equivalence

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Bob has $150 in his savings account and saves $40 per month.

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

A plant is 5cm tall and growing at a rate of 3cm a month.

• y = 5 + 3
• y = 5x + 3
• y = 3x + 5
• y = 3x + 5x

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

Which equation shows the number of bottles left after x days?
A family buys a case of water with 48 bottles and drinks 5 bottles per day.

• y = 48x + 5
• y = -5 + 48x
• y = -5x - 48
• y = 48 - 5x

Sandra has a $20 itunes gift card and spends $3 each month.  Which equation can be used to find how much money Sandra has on her giftcard after x months?

• y = 3x + 20
• y = 3 + 20x
• y = -3x + 20
• y = -20x + 3

Jerry has $20 and makes $7 per hour. Which equation represents the total amount of money Jerry has after working x hours?

• y = 7x + 20
• y = 7 + 20x
• y = 20 + 7

Easy Car Rental charges $8.50 an hour plus a rental fee of $25.50. Which equation represents the total charges for x hours?

• y = 8.5 + 25.5
• y = 25.5 + 8.5x
• y = 8.5 + 25.5x

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

• y = 30 + 12.5x 
• y = 12.5 + 30
• y = 12.5 + 30x

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

• y = 30 + 12.5x 
• y = 12.5 + 30
• y = 12.5 + 30x