What is the equivalent of -40celsius in Fahrenheit scale?

Conversion from Celsius to Fahrenheit is done in three steps:

1. Multiply value in degrees Celsius by 9.

2. Divide result of step 1 by 5.

3. Add 32 to result of step 2.

Conversion formula: [°F] = [°C] * 9 / 5 + 32 = -40 * 9 / 5 + 32 = -40 °F