Exponential Functions Percent Increase and Decrease

How do you increase something by 10%

• Multiply it by 1.1

• Multiply it by 1.01

• Multiply it by 0.1

• Multiply it by 0.01

How do you decrease something by 10%?

• Multiply it by 1.1

• Multiply it by 1.01

• Multiply it by 0.09

• Multiply it by 0.9

Which represents "I started with $700 and increased it by 1% every year.

• y=700(1.1)^x

• y=700(1.01)^x

• y=700(0.99)^x

• y=700(0.9)^x

Which of the following could be represented by A=200(1.1)^t

• I started with $200 and lost 1% per week

• I started with $200 and lost 10% per week

• I started with $200 and gained 1% per week

• I started with $200 and gained 10% per week

Which could represent "I start with 1000 bacteria and gain 5% every minute"

• B=1000(1.5)^t

• B=1000(1.05)^t

• B=1000(5)^t

• None of the above

An investment that started out at $1200 and is losing 12% of its value each month. Write an exponential equation to represent the situation.

A function decays by 33% and starts at 650. Write an exponential equation that represents the situation.

You have $500 in credit card debt. Your credit card charges 15% interest per year. Write an exponential equation that represents the situation.

A sailboat that costs $5,950 decreases in value by 11% per year. How much will the boat be worth after 6 years?

• $5,884.00

• $5,178.97

• $2,992.96

• $2,957.04

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