Where Celsuis and Fahrenheit Meet

Algebra Level 2

You have likely heard of two widely used temperature scales, the Fahrenheit and Celsius scales. Formulae exist that convert between them.

One day, somewhere on Earth, you hold up two thermometers, one in Fahrenheit and another in Celsius, and you find that both seem to be portraying the same value.

What is the value they both are portraying?

-60 Impossible to answer 0 -40 60 40 20 -20

1 solution

Justin Arun
Jul 10, 2020

The formula where °C is converted into °F:

$°F = (°C \times \frac{9}{5}) + 32$

The formula where °F is converted into °C:

$°C = (°F - 32) \times \frac{5}{9}$

Let's use the first formula, where °C is converted into °F.

$°C = (°C \times \frac{9}{5}) + 32$

$°C - (°C \times \frac{9}{5}) = 32$

$\frac{-4}{5} \times °C = 32$

$°C = -32 \times \frac{5}{4}$

$°C = -40$

We may try it out in the °F to °C formula to clarify it further, substituting °C with °F.

$°F = (°F \times \frac{9}{5}) + 32$

$°F - (°F \times \frac{9}{5}) = 32$

$\frac{-4}{5} \times °F = 32$

$°F = -32 \times \frac{5}{4}$

$°F = -40$

So the temperature when both the Celsius and Fahrenheit scales are the same is -40 degrees.

Where Celsuis and Fahrenheit Meet

1 solution

0 pending reports