Simple Interest
What is the formula for simple interest?
I=Prt
If f(x) = 10(2)^x then which of the following represents the value of f(0) ?
1. 1 2. 0
3. 10 4. 20
(3) 10
Which of the following is the equation of an increasing exponential function?
1) y = 4(0.75)^x 2) y = 7(3/2)^x
3) y = 5x - 2 4) y = 3x^2
2) y = 7(3/2)^x
You buy a car for $10,000. It loses value at a rate of 34% per year. Write a model to represent the car's value over time.
What is y = 10,000(0.66)t?
Fill in the blanks: A linear function ____________ or ____________ by the same amount. An exponential function ____________ or ______________ by the same amount.
add/subtracts multiplies/divides
An initial deposit of 5,000.00 dollars is made into a savings account that yields 7.1% interest annually. How much is in the account at the end of 5 years?
1775
Given the function f(x)= (3)(0.5)^x Evaluate the function when x = -4
f(-4) = 48
What has to be greater than 1 for an exponential growth function.
The ratio or base
You buy a car for $10,000. It loses value at a rate of 34% per year. How much value will the car loose in 1 year?
$3400.
Describe the linear function with a negative rate of change.
A line that is decreasing.
To buy a laptop computer, Elaine borrowed $2,000 for 3 years at an annual simple interest rate of 5%. How much interest will she pay if she pays the entire loan off at the end of the third year?
300
The value in dollars, v(x), of a certain car after x years is represented by the equation v(x) = 25,000(0.86)^x. To the nearest dollar, how much is the car worth after four years. 1) 2,589 2) 6,510 3) 13,675 4) 18,490
3) 13,675
The equation A = 1300(1.02)^7 is being used to calculate the amount of money in a savings account. What does 1.02 represent in this equation?
1. 0.02% decay 2. 0.02% growth
3. 2% decay 4. 2% growth
4. 2% growth
You buy a car for $15,000. It loses value at a rate of 17% per year. Write a model to represent the car's value over time.
What is y = 15000(0.83)t?
What is a and b in an exponential function?
a = y intercept b = ratio
What is the difference between simple interest and compound interest?
Simple Interest: Fixed rate on Principle over time
Compound Interest: Fixed rate on [Principle plus Interest earned] on a periodic time frame (weekly, monthly, annually, etc)
Describe an decay function.
It's an exponential function that is decreasing.
You deposit $500 in a bank account with a 7% interest rate that is compounded yearly. How much money will you have in your account in 7 years, rounded to the nearest cent.
$802.89
For a recently released movie, the function y = 119.67(0.61)^x models the revenue earned, y, in millions of dollars each week, x, for several weeks after its release. Based on the equation, how much more money, in millions of dollars, was earned in revenue for week 3 than for week 5? 1) 37.27 2) 27.16 3) 17.06 4) 10.11
3. 17.06
If you were to explain to a friend in Algebra class the major difference between a linear and exponential function, what would you say to them?
Linear functions have a CONSTANT RATE OF CHANGE, while exponential functions have a constant MULTIPLYING FACTOR.
OR
Linear functions graph as a straight line. Exponential functions graph as a curve.
Pat can get a student loan of $10,000 for 10 years at an interest rate of 7%. How much will her total payback to the bank be at the end of the loan?
$17,000
The value in dollars, v(x), of a certain car after x years is represented by the equation v(x) = 25,000(0.86)^x . To the nearest dollar, how much more is the car worth after 2 years than after 3 years? 1) 2,589 2) 6,510 3) 15,901 4) 18,490
1) 2,589
What if a word problem is exponential decay and the percent is 34%. What decimal goes into the formula?
.66
Is this an exponential growth or decay function? What is the growth or decay factor? y = 112(2/3)t?
Decay and the decay factor is (2/3)
what is an asymptote?
What is a line that approaches but doesn't touch the line.