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3rd Grade addition problem


Date: Wed, 16 Nov 94 10:48:24 PST
From: Keith Averell
Subject: grade 3 math

Dear Mr. Math

   My name is Macks Colella.  I want to know the answer to this problem - 
what is 845+904=?  Thanks for your help.

   Macks Colella         


Date: Wed, 16 Nov 1994 15:42:41 -0500 (EST)
From: Dr. Sydney
Subject: Re: grade 3 math

Dear Macks:

        I'm so glad you wrote to Dr. Math!  It is great to hear from you.

You were wondering how to add 845 and 904.  I guess the way I usually
approach problems like this is to write one number above the other, making 
sure that they line up so that the digit that is the farthest right in one 
number always is lined up with the digit that is farthest to the right 
in the other number.  So in this problem, I would write:

                845
               +904
                ---

Then, add, starting with the ones digit, the digit the farthest to the
right.  5+4=9, so I write:

             845
            +904
             ---
             ??9

Then go to the tens digit, the digit just to the left of the ones digit and 
add them together.  So we have:


        845
       +904
        ---
        ?49

Now all that is left to do is add the hundreds digits together.  The
hundreds digit is just to the left of the tens digit.  So, we get for our 
final answer:

        845
       +904
        ---
       1749

Does that make sense to you?  Maybe you could try a few problems on your
own?  Try these, if you would like:

221+358=?

1437+8432=?

98543+34=?  

Write back if you have any more questions!  Good luck!

--Sydney
    
Associated Topics:
Elementary Addition

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