A funny math question containing decimals and fractions

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This is a fun one. Came from the GRE (yeah i know, this is GMAT but this question showed up with a surprise):


Column a:
4.1 + (1/3)

Column b:
5.1-(2/3)

The quantity in Column A is greater.
The quantity in Column B is greater.
The two quantities are equal.
The relationship cannot be determined from the information given.


[spoiler]The two quantities are equal. HOW?!

4.1+(1/3) =4.1+(1/3)

5.1-(2/3)=(4.1 + 1 )-(2/3)
=4.1 + (1-(2/3))
=4.1+ (1/3)

Mathematically when shot into a calculator:

Column a is 4.43, Column b is 4.44 (is what i had)

F YOU ETS!
[/spoiler]

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by DanaJ » Tue Feb 10, 2009 1:12 am
I'm sorry, but they're right about this one. You forget that 1/3 = 0.33333.... or 0.(6) and that 2/3 = 0.6666.... or 0.(3). This means that, since you have an infinity of either 3 or 6 after the 0, then your calculator will give you approximate answers.

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by marcusking » Tue Feb 10, 2009 12:58 pm
Easiest way I have of figuring this out is just removing the .1 from both numbers

Column a:
4.1 + (1/3)

Column b:
5.1-(2/3)


BECOMES


Column a:
4+ (1/3) = 4 & 1/3

Column b:
5-(2/3) = 4 & 1/3

Thus they are equal.