Final answer:
To find the amount of interest earned, use the formula for simple interest. Add the interest earned to the principal to find the total value of the account.
Step-by-step explanation:
To find the amount of interest earned, we'll use the formula for simple interest: Interest = Principal * Rate * Time. In this case, the principal is $1,600, the rate is 4.15% (0.0415 as a decimal), and the time is 18 years. So, the interest earned is $1,600 * 0.0415 * 18 = $1,491.60.
To find the total value of her account after 18 years, we'll add the interest earned to the principal: Total Value = Principal + Interest. So, the total value is $1,600 + $1,491.60 = $3,091.60.