Convert 50 °F to Celsius and kelvin; 310 K to Celsius and Fahrenheit; -25 °C to kelvin and…

Step 1. (a) $\tfrac59 \times 18 = 10\ ^\circ\text{C} = 283.15\ \text{K}$.

Step 2. (b) $310 - 273.15 = 36.85\ ^\circ\text{C}$, and $\tfrac95 \times 36.85 + 32 = 98.33\ ^\circ\text{F}$.

Step 3. (c) $248.15\ \text{K}$, and $\tfrac95 \times (-25) + 32 = -13\ ^\circ\text{F}$.