Final answer:
The annual interest rate for the savings account is 2.49%. This was calculated using the simple interest formula, taking the difference between the final amount and the principal to establish the interest earned over 17 years.
Step-by-step explanation:
To calculate the annual interest rate for a savings account with simple interest, we can use the formula Interest = Principal × Rate × Time. Here, the principal is £13,000, the accumulated amount after 17 years is £18,525, and the total interest earned is therefore £18,525 - £13,000 = £5,525. We can express this in the formula as £5,525 = £13,000 × Rate × 17 years.
To find the Rate, we rearrange the equation to Rate = Interest / (Principal × Time). Plugging in the values we have, Rate = £5,525 / (£13,000 × 17) = 0.0249, or 2.49% when converted to a percentage. Thus, the annual interest rate is 2.49%.
Therefore, the annual interest rate of the account is approximately 2.496%.