Emma deposits $1200 into an account that pays 3% interest, compounded monthly. What is her ending balance after one year?

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2024-0...48.0
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2024-0...48.40
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2024-0...40.01 /
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2024-0...40.30 Al
$1,236.50
$1,709.91

1 answer

To calculate Emma's ending balance after depositing $1200 into an account with a 3% annual interest rate compounded monthly, we can use the formula for compound interest:

\[ A = P \left(1 + \frac{r}{n}\right)^{nt} \]

Where:

  • \( A \) is the amount of money accumulated after n years, including interest.
  • \( P \) is the principal amount (the initial amount of money).
  • \( r \) is the annual interest rate (decimal).
  • \( n \) is the number of times that interest is compounded per year.
  • \( t \) is the number of years the money is invested for.

For Emma's account:

  • \( P = 1200 \)
  • \( r = 0.03 \) (3%)
  • \( n = 12 \) (compounded monthly)
  • \( t = 1 \)

Plugging in the values:

\[ A = 1200 \left(1 + \frac{0.03}{12}\right)^{12 \times 1} \]

Calculating step-by-step:

  1. Calculate \( \frac{0.03}{12} \): \[ \frac{0.03}{12} = 0.0025 \]

  2. Add 1 to the interest rate: \[ 1 + 0.0025 = 1.0025 \]

  3. Calculate \( 12 \times 1 \): \[ 12 \times 1 = 12 \]

  4. Raise \( 1.0025 \) to the power of 12: \[ (1.0025)^{12} \approx 1.0304 \]

  5. Multiply by the principal amount: \[ A \approx 1200 \times 1.0304 \approx 1236.48 \]

Thus, Emma's ending balance after one year is approximately $1,236.48. From your options, the closest is $1,236.50.