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In this problem, we're told that $40 ,000 is borrowed for five years at a 3 % interest.
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Find the interest paid over this period if the interest is compounded as follows.
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Annually, semi -annually, quarterly, monthly, and continuously.
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So first, we're going to do parts a through d because they're pretty similar, and then we'll come back to part e at the end.
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So the formula for determining the amount after the total amount of money after some amount has been deposited, or borrowed for a certain amount of time is the formula a equals p times 1 plus r divided by m to the power of t times m, where p is the amount you started with.
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So in our case, the amount that was borrowed at the beginning was $40 ,000, so that's our p.
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The rate is the interest rate, the annual interest rate, which in our case is 3%.
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If we convert that to a decimal, that's 0 .03.
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So that's what we're going to plug in there.
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T is the total times.
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This is the number of years.
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And in our case, we're told that the money was borrowed for five years.
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So t is equal to five.
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And m is how many times per year our interest is compounded.
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A number of times per year, the interest is compounded.
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Which depends on if it's compounded annually or semi -eurore.
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Annually or quarterly.
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So for example, in part a, we're asked annually if it's compounded annually.
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So that means one time per year, so m is equal to one.
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Part b is semi -annually.
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So that's twice a year.
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So m is equal to two.
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For quarterly, that's once a quarter, so four times a year.
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And finally, monthly, that means it happens once a month, which is 12 times a year.
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So now we have all the information that we need to find our total amount after five years.
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But before we actually do a calculation, we should think about what the problem's asking.
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The problem is not asking how much total will be owed after five years.
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We specifically want to know what the interest will be.
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So after we find our answers, so after we plug all this in, that's the number that we get is going to be the total amount that we owe.
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But in this problem, we only are caring about how much interest is paid.
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So what we should do is we should subtract the original amount.
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So subtract $40 ,000 because that was money that we owed anyway because we borrowed the $40 ,000.
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So what we want to know is how much interest we're paying.
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So on top of paying back the $40 ,000, how much interest will we owe? so we should find this for each of these four parts.
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Let's do this on a new page.
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So in part a, we're going to look at the equation...