Unit 6: Investing Strategies & Exponential Functions Review

Growth/Decay

100

A town with a population of 5,000 grows at a rate of 3% a year. What is the population in 10 years?

What is 6,719

200

Amy makes an initial investment of $3,000.  The investment loses 4% a year.  Find the amount Amy has at the end of 8 years?

What is $2,164.17

300

A solution of 250ml loses 7.25% of it's mass every day.  How many ml after 10 days?

What is 117.8ml

400

John's Corvette worth $15,500 loses 4.25% of its value every year.  What is the vette worth after 10 years?

What is $10,039.67

500

A certain microbe of 3.25mg multiplies at a rate of .03% an hour. How many miligrams is the microbe at the end of 1 day?

What is 3.27mg

Continuous Interest

100

You invest $1,050 at 4.24% interest compounded continuously.  How much is in account after 5 years? Round to nearest cent. 

What is $1,297.96

200

$500 compounded continuous for 3 years at 5%

What is $580.92

300

John bought a laptop and financed $750.  The interest was compounded continuously at 2.25%.  How much interest was accrued if no payment was made after 2 years? 

What is $34.52

400

If Jimmy invested $4,500 into the bank at a rate of 11.5% compounded continuous for 25 years, how much will he have in his account?

What is $79,764.41

500

You invest $1 compounded continuous at 10% rate for 50 years.  How much do you have?

What is $148.41

Definitions

100

The interest rate charged on a principal

What is Rate

200

The amount of money invested or borrowed

What is Principal

300

When money is compounded four times a year

What is Quarterly

400

Interest + Principal

What is Total or Amount

500

When money is compounded two times a year

What is Semiannually

Logs

100

Solve 2^x=15

What is 3.907

200

Convert log₁₂144=2

12²=144

300

Solve 5^z=145

What is 3.092

400

Solve 6*4^x-18=165

What is 2.465

500

Solve 6+17*7^x=254

What is 1.377

Compound Interest Word Problems

100

John invested $16,000 at 3% compounded annually.  How long would it take for him to have $24,500?

What is 14.4 years

200

Mary borrowed $450 at 8% compounded continuously.  How much would interest does she need to pay back after 3 years? 

What is $122.06

300

Carlos invested $147,000 at a rate compounded continuously for 5.5 years. If his goal is to have $300,000 at the end of 5.5 years, what is the rate?

What is 12.97%

400

Jeremy starts with $5000 in an investment account and wants to double his money.  The interest rate is 4.5%.  Estimate how long it will take to double his money?

What is 16 years

500

Ken invested $372.28 at 7% compounded annually for 2 3/4 years. Find A.

What is $448.41