Question 1170228
Start is from one whole pie, 1 pie.


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One elf ate 1/6 of a pie. Another elf ate 3/8 of the pie. A third elf ate 1/4 of the pie.
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How much is still uneaten?

{{{1-1/6-3/8-1/4}}}


Look at the denominators.   
6, 8, 4.
If you are trying to use prime number factorizations to find the lowest common denominator, then:
2*3, 2*2*2, 2*2;
You need 1 of 3 factor and 3 of 2 factor
which is {{{(3)(2*2*2)}}}, which is same as 24.


Raise all your terms to higher terms of denominator 24.
{{{24/24-4/24-9/24-6/24}}}--------now compute this, and simplify if possible.