Identifying Linear and Exponential Functions in Real Life

A car rental company charges a flat fee of $30 per day to rent a car. If you rent the car for 5 days, how much will it cost? Is this a linear or exponential function?

• $200, linear function

• $150, linear function

• $150, exponential function

• $100, linear function

A population of bacteria doubles every hour. If you start with 10 bacteria, how many will there be after 3 hours? Is this a linear or exponential function?

• 30 bacteria after 3 hours. This is a linear function.

• 100 bacteria after 3 hours. This is an exponential function.

• 80 bacteria after 3 hours. This is an exponential function.

• 40 bacteria after 3 hours. This is a linear function.

You save $50 every month in a savings account. How much will you have saved after 6 months? Identify the type of function represented by your savings.

• $300

• $150

• $600

• $250

A smartphone app has 1,000 users and the number of users increases by 10% each month. How many users will the app have after 2 months? Identify the type of function.

• 1210

• 1100

• 1500

• 1300

You earn $15 per hour at your job. If you work 20 hours a week, how much will you earn in 4 weeks? Is this a linear or exponential function?

• $1200. This is a linear function.

• $800. This is an exponential function.

• $1000. This is a quadratic function.

• $600. This is a linear function.

A certain investment grows by 5% each year. If you invest $1,000, how much will it be worth after 3 years? Identify the type of growth.

• $1,200.00

• $1,100.00

• $1,050.00

• $1,157.63

A train travels at a constant speed of 60 miles per hour. How far will it travel in 3 hours? Is this a linear or exponential function?

• 180 miles, exponential function

• 240 miles, linear function

• 150 miles, exponential function

• 180 miles, linear function

A video game character gains experience points exponentially, starting with 100 points and doubling every level. How many points will the character have after reaching level 4? Identify the type of function.

• 400 points

• 800 points

• 1600 points

• 3200 points

You are collecting stickers and start with 5 stickers. You collect 3 more stickers each week. How many stickers will you have after 8 weeks? Is this a linear or exponential function?

• 25 stickers

• 40 stickers

• 32 stickers

• 29 stickers