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2/3x -1/2x =(4x-3x)/6 = x/6 = 1/6x
1/4x+1/3x=(4x+4x)/12=7x/12=7/12x
-7/12y-2/5y=(-7y-10y)/12=-17/12y
8/15y-2/5y=(8y-6y)/15=2/15y
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2/3x -1/2x =(4x-3x)/6 = x/6 = 1/6x
1/4x+1/3x=(4x+4x)/12=7x/12=7/12x
-7/12y-2/5y=(-7y-10y)/12=-17/12y
8/15y-2/5y=(8y-6y)/15=2/15y