Question 666169
(1).  
Since these already have common denominators, subtract numerators then whole numbers.
{{{8 (3/4)}}}
-{{{3 (1/4)}}}
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{{{highlight_green(5 (2/4))}}}
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(2).
Since these do not have a common denominator, find the greatest common multiple, which is 12.  So,
{{{7(5/12)}}}
-{{{2(3/4)(3/3)}}}= {{{2(9/12)}}}
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Subtract numerators first, but since you have to borrow, take from the whole number.  7 is the same as {{{6(12/12)}}} 
so add {{{12/12}}} to {{{5/12}}} to get {{{17/12}}}
{{{6(17/12)}}}
-{{{2(9/12)}}}
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Now subtract the numerators, then the whole numbers
{{{4(8/12)}}} which simplifies to {{{highlight_green(4(2/3))}}} since 4 goes into 8 and 12.
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