Convert each mixed # to an imp. fraction:
2 1/4 + 6 1/8=
9/4 + 49/8 <--- There, now then when adding and subracting fractions, there needs to be a common denominator:
9/4 ---> 18/8 because 9 x 2 = 18
4 x 2 = 8
so now, 18/8 + 49/8, add the numerators ---> 67/8
now simplify, 67/8 = 8 3/8
