To calculate the amount of interest that Kaira will earn at the end of the 3-year term, we'll first consider the deposits she made and the interest earned on each:
- Kaira deposits $600 at the beginning of each year for 3 years.
- The interest rate is 4.75%, which we will convert to a decimal \( r = 0.0475 \).
- Using the formula \( x = 1 + r = 1 + 0.0475 = 1.0475 \).
Now we plug this into the equation provided for \( C(x) \): \[ C(x) = 600 x^3 + 600 x^2 + 600 x \]
Calculating each term:
- For the first deposit (made at the beginning of Year 1), it earns interest for 3 years: \[ 600 x^3 = 600 (1.0475)^3 \]
- For the second deposit (made at the beginning of Year 2), it earns interest for 2 years: \[ 600 x^2 = 600 (1.0475)^2 \]
- For the third deposit (made at the beginning of Year 3), it earns interest for 1 year: \[ 600 x = 600 (1.0475) \]
Now, let's calculate each component:
Calculate \( (1.0475)^3 \):
\[ (1.0475)^3 \approx 1.148882 \]
So, \[ 600 \cdot 1.148882 \approx 689.33 \]
Calculate \( (1.0475)^2 \):
\[ (1.0475)^2 \approx 1.09796 \]
So, \[ 600 \cdot 1.09796 \approx 658.78 \]
Calculate \( (1.0475) \):
So, \[ 600 \cdot 1.0475 \approx 628.50 \]
Now, combine these values to get \( C(x) \):
\[ C(x) \approx 689.33 + 658.78 + 628.50 = 1976.61 \]
Calculate the total deposits:
Kaira deposited a total of 3 deposits of $600 each: \[ \text{Total Deposits} = 3 \cdot 600 = 1800 \]
Calculate the interest earned:
\[ \text{Interest Earned} = C(x) - \text{Total Deposits} = 1976.61 - 1800 = 176.61 \]
Conclusion:
The amount of interest that Kaira will earn at the end of the 3-year term is approximately $176.61 (rounded to two decimal places).