7/12-(1/4)
first you need a common denominator which is 12
in the first fraction we already have a 12, so we don't need to multiply times anything, but the second fraction already has a 4, so what times 4 is 12, 3. So we multiply top and bottom by 3.
7(1)-1(3)/12=(7-3)/12=4/12=1/3