you’re adding right?
if so, it would be
7/8 + 3/8 = 10/8 (divide by 2) = 5/4
the reason you divide by 2 is because every fraction must be in lowest terms.
so;
10 divide by 2
—
8 divide by 2
whatever you do to the numerator (top) you must do the the denominator (bottom)