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Inches and Feet in Decimal Form

Date: 7/16/96 at 0:48:32
From: dmcmnm
Subject:Inches and Feet in Decimal Form

I know that 12 inches equal 1.0 feet and 6 inches equal 0.50 feet. How 
do I convert 2 inches or 1 inch into a decimal expression of feet? 
What about fractions of inches, like 3/4ths of an inch? Is there a way 
to do this?  Is there a table for this kind of conversion or a formula 
I can use?  

Let's say I have a room that is {16ft 10 5/8in X 15ft 11 1/8in}.  How 
would I convert that into decimals such as {16.? X 15.?}

Date: 7/16/96 at 9:42:52
From: Doctor Paul
Subject: Re: Inches and Feet in Decimal Form

In the general form where you have inches and want to convert to feet 
you divide the number of inches you have by 12. If you had 6 inches, 
you would have 6/12 or 1/2 foot, right?

You've got a little bit more complicated problem with 16ft 10 5/8 
inches. Same concept though. We need to figure out how many inches you 
have and then divide by 12.  

If you had 16 feet 6 inches, how would you do that? You would say 
16 ft + (6 inches/12 inches) = 16.5 feet, right? You would convert 
the inches to feet and then add that number of feet to the original 
number of feet (in this case 16 feet).

We're going to do the same thing. Let's figure out how many feet 
10 5/8 inches is and then add 16 to that number.  

Before we can convert 10 5/8 to feet, we have to have it as a decimal 
representation. Note that 10 5/8 is really just saying 10 + 5/8. 
Right?  So let's divide out 5/8. I get .625.

So 10 5/8 is the same as 10.625  Now we can divide this by 12 the way 
we did previously with a more simple problem.  10.625/12 = .88541667 
feet.  So 10 and 5/8 inches is .88541667 feet.  

Now we add this to 16 feet and get the grand total:

  16.88541667 feet

I hope this is clear.  I've tried to make it as simple as possible.  
I'll leave the conversion of 15 feet 11 1/8 inches to you.  

-Doctor Paul,  The Math Forum
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Associated Topics:
Elementary Fractions
Elementary Terms & Units of Measurement
Middle School Fractions
Middle School Terms/Units of Measurement

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