Question: Using $\pi$, not an approximation, what is the circumference of a circle with a radius of $10.1$ in? Round to the tenths place.
1. **State the problem:** We need to find the circumference of a circle with radius $r = 10.1$ inches using $\pi$ exactly, then round the result to the tenths place.
2. **Formula:** The circumference $C$ of a circle is given by the formula:
$$C = 2 \pi r$$
3. **Substitute the radius:**
$$C = 2 \pi \times 10.1$$
4. **Calculate the exact expression:**
$$C = 20.2 \pi$$
5. **Approximate using $\pi \approx 3.14159$ to round:**
$$C \approx 20.2 \times 3.14159 = 63.466118$$
6. **Round to the tenths place:**
$$63.466118 \approx 63.5$$
7. **Answer:** The circumference is approximately $63.5$ inches.
**Therefore, the correct choice is:** 63.5 in.