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Addition of 1 and 99999999.999999


Date: 1 May 1995 08:52:38 -0400
From: Ahmad Hajiyahya
Subject: (none)

Help

1+99999999999999.9999999=?


Date: 1 May 1995 10:33:44 -0400
From: Dr. Sydney
Subject: Re: your mail

Hi Ahmad,

If instead, you really don't mean those last 7 9's after the decimal point
to go on forever, but instead you see the second number as having only 7 (as
opposed to infinite) 9's after the decimal point, you would approach the
problem just as you would any other simple addition problem.  I would write
the numbers on top of one another so that the decimal points line up
(remember that 1 = 1.0000000, right?), then add corresponding columns,
making sure you "carry" when necessary.  The first steps should look like
this:

                         11
              99999999999999.9999999
                         + 1.0000000
              ----------------------
             *************00.9999999      

See if you can finish this one up (fill in the stars).  Thanks for the
question!

---Sydney, "Dr. Math"


Date: 1 May 1995 10:24:13 -0400
From: Dr. Ken
Subject: Re: .99999999999

Hello there!

Something to keep in mind is that .99999999999999999..... = 1.  So you could
simplify your problem to read 1+100000000000000=?, and then it's more clear
that the answer is 100000000000001.  Thanks for the question!

-K
    
Associated Topics:
Elementary Addition

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