Interpreting Exponential and Linear Functions

Suppose a culture of bacteria begins with 5000 cells and dies by 30% each year. Write an equation that represents this situation.

• y=5000(0.7)^x
• y=30(5000)^x
• y=5000(1.3)^x
• y=5000x^x

Which of the following functions shows an initial amount of $15 and an increase of 35% each year?

• y = 15(35)^x
• y = 15(1.35)^x
• y = 15(0.35)^x
• y = 35(1.15)^x

A collectible car has been going up in price by 10% each year. If the car is already worth $29,000, how much will the car be worth in 5 years?

• $0.29
• $2,900,000,000
• $46,704.79
• $145,000

The amount of ibuprofen (medicine for headaches) breaks down by 30% each hour. If a person took a 200 milligram ibuprofen, how much will be left after 3 hours?

• 5.4 mg
• 68.6 mg
• .0054 mg
• 2,400,000 mg

The value of a car purchased for $20,000 decreases at a rate of 12% per year. What will be the value of the car after 3 years?

• $12,800.00

• $13,629.44

• $17,600.00

• $28,098.56

A driving range charges $4 to rent a golf club plus $2.75 for every bucket of golf balls you hit. Write an equation that shows the total cost c of hitting b buckets of golf balls.

• c = 2.75b + 4
• c = 2.75b
• c =  4b- 2.75
• c = 2.75b - 4

The equation below represents an elevator's height after an amount of seconds. Using this equation, what should the height of the elevator be after 14 seconds?
y = -3.8x + 290

• 80
• 236.8
• -80
• 72.6

What is the meaning of the slope in the context of the problem?

• It costs $3 for each book.
• The cost of 3 books.
• Each book costs $1.
• $1 for 3 books.

Which residual plot shows that a linear regression model would be most appropriate?

• a
• b
• c

Is this table linear, quadratic, exponential, or none of the above?

• linear, because the differences are constant

• quadratic, because the differences are linear

• exponential, because there is a multiplying pattern

• none of the above