1. **State the problem:** We need to find the simple interest rate $r$ for which a principal of 15200 earns an interest of 421 from July 15 to November 17 in the same year. 2. **Formula for simple interest:** $$I = P \times r \times t$$ where $I$ is the interest earned, $P$ is the principal, $r$ is the rate (in decimal), and $t$ is the time in years. 3. **Calculate the time $t$:** From July 15 to November 17: - July 15 to July 31 = 16 days - August = 31 days - September = 30 days - October = 31 days - November 1 to 17 = 17 days Total days = 16 + 31 + 30 + 31 + 17 = 125 days Since the year has 365 days, time in years is: $$t = \frac{125}{365}$$ 4. **Plug values into the formula and solve for $r$:** $$421 = 15200 \times r \times \frac{125}{365}$$ Rearranging for $r$: $$r = \frac{421 \times 365}{15200 \times 125}$$ 5. **Calculate $r$:** $$r = \frac{153665}{1900000} \approx 0.08087$$ 6. **Convert to percentage:** $$r \approx 8.09\%$$ **Final answer:** The simple interest rate is approximately 8.09% per annum.