The equation for this is:
F = P(1+i)ⁿ
where
F is the present accounts balance
P is the initial deposit
i is the interest rate
n is the number of months
The interest rate is nominal which is 2.9% per year compounded monthly. Since there are 12 months in a year, that is equal to an effective interest rate of 0.24167% per month compounded monthly (i = 0.0024167). In 9 years, there are a total of 108 months, so n=108.
<span>$2033.88 = P(1+0.0024167)</span>¹⁰⁸
P = $1567.147
This is a perfect example of exponential decay. In this case the growth factor should be represented by a fraction, and it is! This forest, starting out with apparently ( 800? ) pine trees, has a disease spreading, which kills 1 / 4th of each of the pine trees yearly. Therefore, the pine trees remaining should be 3 / 4.
Respectively 3 / 4 should be the growth factor, starting with 800 pine trees - the start value. This can be represented as such,
- where a = start value, b = growth factor, t = time ( <em>variable quantity</em> )
____
Thus, the function 
can model this problem. The forest after t years should have P( t ) number of pine trees remaining.
Answer: 1.25n
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Explanation:
Erica sells bracelets for $2 each. If she makes and sells n of them, then she gets 2n dollars of revenue.
Making n bracelets cost her a total of 0.75n dollars because each bracelet costs 0.75 dollars, or 75 cents.
Subtract the revenue and cost to get the profit
profit = revenue - cost
profit = 2n - 0.75n
profit = (2-0.75)n
profit = 1.25n
The expression 1.25n means that she earns $1.25 in profit per bracelet sold.
<h2>Answer</h2>
Or as ordered pairs: 
<h2>Explanation</h2>
Lets solve our system of equations step by step
equation (1)
equation (2)
1. Solve for 
in equation (2)
equation (3)
2. Replace equation (3) in equation (1) and solve for 
or 
3. Replace the values of in equation (3) and solve for 
- For
or 
- For
or 
So, the solutions of our system of equation are:
