1. **State the problem:** Compute the product of $527_8$ and $673_?$ where the base of the second number is unknown. 2. **Analyze the problem:** The first number is in base 8 (octal). The second number's base is not given, so we cannot directly multiply without knowing the base. 3. **Convert $527_8$ to decimal:** $$527_8 = 5 \times 8^2 + 2 \times 8^1 + 7 \times 8^0 = 5 \times 64 + 2 \times 8 + 7 = 320 + 16 + 7 = 343_{10}$$ 4. **Interpret $673_?$:** The digits are 6, 7, and 3. For the base to be valid, the base must be greater than the largest digit, which is 7. So the base must be at least 8. 5. **Since the base is unknown, the problem cannot be solved without additional information.** **Final answer:** Cannot compute $527_8 \times 673_?$ without knowing the base of the second number.