X(11/12-1/4)=3/8
x(11/12-3/12)=3/8
8/12x=3/8
x=3/8*12/8
x=9/16
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x(1 2/3+5/9)=2/3
x(1 6/9+5/9)=2/3
1 11/9x=2/3
x=2/3*9/20
x=3/10
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x:(4 1/3-3)=1 1/2
x:1 1/3=1 1/2
x:4/3=3/2
x=3/2*4/3
x=2
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