<PRE><B>Question 67177</B>
Let x=the weight of the WHOLE stack of paper (in pounds)

Now, we know 1 book equals 1 pound and 1 book AND 1/3 of the stack (x) = 3 books and 1/4 of the stack (x).  This is just a matter of solving for x!

1 + {{{1/3}}}x = 3 + {{{1/4}}}x        --- subtract 1 from both sides
1 + {{{1/3}}}x - 1 = 3 + {{{1/4}}}x - 1
{{{1/3}}}x = 2 + {{{1/4}}}x     ---- subtract {{{1/4}}}x from both sides
{{{1/3}}}x - {{{1/4}}}x = 2  --- find the common denominator 
{{{4/12}}}x - {{{3/12}}}x = 2
{{{(4-3)/12}}}x = 2
{{{1/12}}}x = 2     ---- multiply both sides by 12
12 * {{{1/12}}}x = 2 * 12  and ultimately 
x = 24.

You can check this answer by plugging back into the original equation.

1 + {{{1/3}}} * 24 = 3 + {{{1/4}}} * 24
1 +_8 = 3 + 6
9 = 9

So 1 stack of paper weighs 24 pounds! 

Hope this helps!!

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