To convert degrees Fahrenheit (°F) to degrees Celsius (°C), you can use the following formula:
\[ °C = \frac{(°F - 32) \times 5}{9} \]
Plugging in 90°F:
\[ °C = \frac{(90 - 32) \times 5}{9} \] \[ °C = \frac{(58) \times 5}{9} \] \[ °C = \frac{290}{9} \] \[ °C \approx 32.22 \]
Therefore, 90°F is approximately 32.22°C.