## Trigonometry (10th Edition)

We can express the angle in degrees: $\theta = 3^{\circ}20' = (3 + \frac{20}{60})^{\circ} = 3.33^{\circ}$ We can convert the angle to radians: $\theta = (3.33^{\circ})(\frac{\pi~rad}{180^{\circ}}) = 0.05812~rad$ We can approximate the length $L$ of the train: $L \approx \theta ~r$ $L \approx (0.05812~rad)(3.5~km)$ $L \approx 0.20~km$ $L \approx 200~m$ The length of the train is approximately 200 m.