1. The problem asks for the measure of each interior angle of a regular polygon with 10 sides (a regular decagon). 2. The formula to find the measure of each interior angle of a regular polygon with $n$ sides is: $$\text{Interior angle} = \frac{(n-2) \times 180^\circ}{n}$$ 3. For a decagon, $n = 10$. 4. Substitute $n = 10$ into the formula: $$\text{Interior angle} = \frac{(10-2) \times 180^\circ}{10} = \frac{8 \times 180^\circ}{10}$$ 5. Calculate the numerator: $$8 \times 180^\circ = 1440^\circ$$ 6. Now divide by 10: $$\frac{1440^\circ}{10} = 144^\circ$$ 7. Therefore, each interior angle of the regular decagon measures $144^\circ$. 8. Since the problem asks to round to the nearest tenth if necessary, and $144^\circ$ is exact, the final answer is $144.0^\circ$.