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Each year a certain amount of money is deposited in an account which pays an

annual interest rate of so that at the end of each year the balance in the account is multiplied by a growth factor of . $500 is deposited at the start of the irst
year, an additional $200 is deposited at the start of the next year, and $600 at the start of the following year.
a. Write an expression for the value of the account at the end of three years in
terms of the growth factor .
Please do step by step on how you got the answer

User Aberger
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1 Answer

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Answer & Step-by-step explanation:

To find an expression for the account's value at the end of three years in terms of the growth factor, we need to consider the deposits made at the start of each year and the interest earned.

Let's break it down step by step:

1. Year 1: $500 is deposited at the start of the first year. At the end of the year, it will grow with the interest rate, which we'll denote as "r." So, the value at the end of the first year is $500 * (1 + r).

2. Year 2: In the second year, an additional $200 is deposited at the start of the year. The balance at the beginning of the second year (the end of the first year) is $500 * (1 + r). This balance will then grow with the interest rate for one year. So, at the end of the second year, the value is:

$500 * (1 + r) * (1 + r) + $200

We can simplify this to:

$500 * (1 + r)^2 + $200

3. Year 3: In the third year, an additional $600 is deposited at the start of the year. The balance at the beginning of the third year (the end of the second year) is $500 * (1 + r)^2 + $200. This balance will then grow with the interest rate for one year. So, at the end of the third year, the value is:

($500 * (1 + r)^2 + $200) * (1 + r) + $600

Now, we have an expression for the value of the account at the end of three years in terms of the growth factor "r":

V = ($500 * (1 + r)^2 + $200) * (1 + r) + $600

This expression represents the account's value at the end of three years with the given deposits and annual interest rate, and it's in terms of the growth factor "r."

User Karim Tarabishy
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