This is probably not the method normally used but to make it easier for myself, I just turn them into improper fractions rather than mixed fractions. With that being said:
3 3/4 turns into 15/4
Turn the denominator into 8 to match the second mixed fraction
30/8 (since the equation equals 2 the second has to be 16/8 to match (30/8-16/8)
Turn 16/8 into mixed fraction and that's your answer... this was probably very confusing for you though... sorry ;-;
