A six-month \( \$ 6000 \) treasury bill sold for \( \$ 5613 \). What was the simple annual discount rate? The discount rate was \( \square \% \). (Type an integer or decimal rounded to one decimal place as needed.)

To find the simple annual discount rate, we start by determining the discount amount, which is the difference between the face value and the purchase price. The discount amount is \( 6000 - 5613 = 387 \). Next, we can use the formula for the discount rate: \[ \text{Discount Rate} = \frac{\text{Discount Amount}}{\text{Face Value}} \times \frac{360}{\text{Days to Maturity}} \] In this case, the days to maturity for the 6-month treasury bill is 180 days. Plugging in the numbers, we have: \[ \text{Discount Rate} = \frac{387}{6000} \times \frac{360}{180} \] Calculating this gives: \[ \text{Discount Rate} = \frac{387}{6000} \times 2 = 0.1289 \text{ or } 12.89\% \] Rounding to one decimal place, the simple annual discount rate is \( 12.9\% \).