Answer:
See Below
Step-by-step explanation:
The question is asking:
After how many years, 20,000 will become 500,000 at an annual interest of 11.5%?
So, we need compound growth formula shown below to solve this:

F is future value
P is present amount
r is rate of interest
t is the time of year
Given,
F = 500,000
P = 20,000
r = 11.5% = 11.5/100 = 0.115
t is what we want to find

Now, we take natural log of both sides and solve for t:

Its is going to take about 29.57 years, rounding, 30 years
Question
a) What is the decay factor?
b) What is the percent decrease?
c) Estimate the number of black and white TV's sold in 1999.
Answer:
a. Decay factor = 0.85
b. Percent decrease = 15%
c. 19.363 million TVs were sold
Step-by-step explanation:
Given

Solving (a): The decay factor
An exponential function has the form

Where b is:

By comparison:

Solving (b): Percentage decrease:
Percentage decrease P is calculated as follows:

Substitute 0.85 for b


Convert to percentage


Solving (c): TVs sold in 1999
First, we need to determine the value of t for 1999
In 1997, t= 0
In 1998, t= 1
In 1999, t= 2
So, we substitute 2 for t in: 



9514 1404 393
Answer:
- monthly payment $690.25
- total interest $123,490
- total repaid $248.490
- difference from rent $9.75
Step-by-step explanation:
Frank's monthly payment will be $690.25.
The total of all payments will be $690.25 × 360 = $248,490.00.
The interest Frank will pay is $248,490 -125,000 = $123,490.00.
The difference between Frank's rent and his loan payment is ...
$700 -690.25 = $9.75
Well I think that for this problem we should multiply 3x1/3 which is 1 whole. Sorry if I'm incorrect.