Trigonometry (10th Edition)

$125^{\circ}$
The big hand is at $\frac{10}{60}360^{\circ}=60^{\circ}$, compared to twelve o'clock, the small hand is at $\frac{6}{12}360^{\circ}+\frac{10}{60}\frac{1}{12}360^{\circ}=180^{\circ}+5^{\circ}=185^{\circ}$. Therefore, the angle is $185^{\circ}-60^{\circ}=125^{\circ}$