Converting Fahrenheit to Celsius

Math instructor presents how to convert Fahrenheit to Celsius. Includes accurate calculation and mental math calculation for estimation.

Transcript

Welcome to Math with Mr. J! In this video, I'm going to cover how to convert degrees Fahrenheit to degrees Celsius, and we have two examples that we're going to go through together. In order to get this down, the formula that we're going to use is at the top of the screen. We're going to take the degrees Fahrenheit that we're given and subtract 32. Then we're going to divide by 1 and 8 tenths or 1.8.

I also added an estimation formula at the top of the screen. This estimation formula can be used to find an approximate or close conversion using mental math. So I'll go through the exact conversions and then how to estimate. Let's jump into number one where we have 95 degrees Fahrenheit.

The first thing we want to do is rewrite the formula that we're going to use to convert this: degrees Fahrenheit minus 32, divided by 1 and 8 tenths. Then we plug in the degrees Fahrenheit that we want to convert, the number that we're given, so 95 degrees Fahrenheit. Let's plug that into our formula:

95 - 32 = 63, and 63 ÷ 1.8 = 35. So, 95 degrees Fahrenheit equals 35 degrees Celsius.

Now, as far as the estimation, we can use this formula: degrees Fahrenheit minus 30, divided by 2. So we'll plug in our 95 here and solve: 95 - 30 = 65, and 65 ÷ 2 = 32.5 or 32 and 5/10 degrees Celsius. That is our estimate, and it did give us a pretty close approximate conversion there.

Let's move on to number two where we have 17 degrees Fahrenheit. We will start by rewriting our formula: degrees Fahrenheit minus 32, divided by 1 and 8 tenths. So we'll plug in 17:

17 - 32 = -15, and -15 ÷ 1.8 = -8.3̅. So, the exact conversion is -8.3̅ degrees Celsius. We can round that to the nearest whole degree, which would be -8 degrees Celsius.

As far as the estimate, let's rewrite our formula: degrees Fahrenheit minus 30, divided by 2. So we have:

17 - 30 = -13, and -13 ÷ 2 = -6.5 or -6 and 5/10 degrees Celsius.

So, there you have it! That's how you convert degrees Fahrenheit to degrees Celsius. I hope that helped. Thanks so much for watching until next time!