Exponential Functions

A website has 267,500 subscribers and has reached its peak. The number of subscribers is decreasing at a rate of 8% each month.​How many subscribers will there be after 7 weeks? (Round to the nearest whole number.)

• 477,679 subscribers

• 149,800 subscribers

• 149,224 subscribers

• 458,448 subscribers

Tags

CCSS.HSF-LE.A.1C

Which function represents an exponential growth?

• $f\left(x\right)=\left(.97\right)^x$

• $f\left(x\right)=\left(1.00\right)^x$

• $f\left(x\right)=\left(1.01\right)^x$

• $f\left(x\right)=\left(.9\right)^x$

Tags

CCSS.HSF-LE.A.1A

What is the decay rate for the following exponential function?

 $f\left(x\right)=54\left(.94\right)^x$  

• 6%

• 94%

• 54%

• 0.06%

Tags

CCSS.HSF-IF.C.8B

The value of a sports car each year is given by the following expression:

 $32,000\left(0.82\right)^x$  
What is the meaning of the common ratio?

• The value of the sports car is decreasing by 28% each year.

• The value of the sports car is decreasing by 82% each year.

• The starting cost of the sports car is $32,000.

• The value of the sports car is decreasing by 18% each year.

Tags

CCSS.HSF-IF.C.8B

Write a function for the following statement.

Fiona has $500 in her savings account and plans to save $45 each month.

• $f\left(x\right)=45x+500$

• $f\left(x\right)=500x+45$

• $f\left(x\right)=500\left(45\right)^x$

• $f\left(x\right)=45\left(500\right)^x$

Tags

CCSS.HSF-BF.A.1A

Fiona has $500 in her savings account and plans to save $45 each month.

How much money will Fiona have in her account after 12 months?

• $540

• $1,040

• $557

• $6,045

Tags

CCSS.HSF.BF.A.2

Write a function for the following statement.

Alex invests $345 in an account that earns 5% interest compounded annually.

•  $f\left(x\right)=0.05x+345$ 

•  $f\left(x\right)=1.05x+345$ 

•  $f\left(x\right)=345\left(0.05\right)^x$ 

•  $f\left(x\right)=345\left(1.05\right)^x$ 

Tags

CCSS.HSF-BF.A.1A

Alex invests $345 in an account that earns 5% interest compounded annually.

What is Alex's balance after 3 years? (Round to the nearest cent)

• $460

• $348.15

• $399.38

• $295.79

Tags

CCSS.HSA.CED.A.1

CCSS.HSF.BF.A.1

CCSS.HSF.LE.A.1

CCSS.HSF.LE.A.2

Write a function for the following statement.

Scientists studied the population of a species of bats in some caves in Missouri from 1983 to 2003. In 1983, there were 185,600 bats living in the caves. That number decreased by about 11% annually until 2003.

•  $f\left(x\right)=-0.89x+185,600$ 

•  $f\left(x\right)=-0.11x+185,600$ 

•  $f\left(x\right)=185,600\left(.89\right)^x$ 

•  $f\left(x\right)=185,600\left(0.11\right)^x$ 

Tags

CCSS.HSF.LE.A.2

Scientists studied the population of a species of bats in some caves in Missouri from 1983 to 2003. In 1983, there were 185,600 bats living in the caves. That number decreased by about 11% annually until 2003.

How many bats were there in 2003? (Round your answer to near whole number.)

• 18,046 bats

• 1,664 bats

• 16,893 bats

• 1,021 bats

Tags

CCSS.HSF-LE.A.1C