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Converting Fahrenheit to Celsius

Date: 9/29/95 at 8:47:9
From: Anonymous
Subject: Temperature

Is there a temperature that is the same on both the Celsius and 
Fahrenheit scales?

Date: 9/29/95 at 11:20:0
From: Doctor Ken
Subject: Re: Temperature


Nice question.  There's a formula that you can use to get from 
Fahrenheit to Celsius: it's 

c = (f-32) * 5/9 .

The way we get this formula is to say that when f is 32, c is 0, so 
we must have c = (f-32)k, where k is some constant.  To find the 
constant, we know that when f = 212 (boiling), c = 100.  So 

100 = (212-32)k
100 = 180k
  k = 5/9

So with the formula c = (f-32) * 5/9, we can figure out when f = c.  
If you want more hints, don't hesitate to write back.

-Doctor Ken,  The Geometry Forum

Date: 9/29/95 at 17:44:22
From: Doug Zink
Subject: Re: temperature

Dear sir, my question was if there is a temperature that is the 
same for both Celsius and Fahrenheit?     Doug

Date: 9/29/95 at 23:25:43
From: Doctor Ken
Subject: Re: temperature


The formula I gave you was one that converted Fahrenheit to 
Celsius.  To solve your problem, you'd say "when is f equal to c,"  
i.e. solve the equation 

x = (x-32) * 5/9.

Does that make sense?

-Doctor Ken,  The Geometry Forum

Date: 9/30/95 at 1:23:37
From: Doctor Andrew
Subject: Re: temperature

Dr. Ken said:
>So with the formula c = (f-32) * 5/9, we can figure out when f = c.

If there are values of c and f, where f=c, that satisfy that equation,
and that are reasonable temperatures (greater than absolute 0), then 
there is such a temperature.  Finding that temperature could be
tough if you don't know much algebra, but we'd be glad to give you 
some help.

You could also use your calculator to test different temperatures, 
until you get pretty close to the right one (try a value for f and 
see if you get the same value as the result of the formula).  There 
is a value that is greater than absolute 0 that will work with the 
formula.  Can you figure out what it is?

-Doctor Andrew,  The Geometry Forum
Associated Topics:
Middle School Temperature

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