Turning a Sentence into a Variable Expression

Date: 9/7/96 at 14:12:9
From: Anonymous
Subject: Turning a Sentence into a Variable Expression

I have a problem expressing:

"The difference when a number T is subtracted from 18"

Which number goes first? How do I write this out?

Date: 9/8/96 at 13:33:1
From: Doctor Robert
Subject: Re: Turning a Sentence into a Variable Expression

If T is subtracted from 18, then the number 18 becomes smaller, so the 
correct expression is 18 - T.  (Try it for different values of T like
1,3,5, for example, and you'll see how this works).  Try looking at 
another problem: "Reduce T by 18." The correct expression for this 
would be T - 18.

Practice on problems like these:  
Three less than x
x less than thirteen

Cheers.

-Doctor Robert,  The Math Forum
 Check out our web site!  http://mathforum.org/dr.math/