find the LCM of the Denominator of
1/6 + 1/7 + 1/8 - 9 3/8..if you get the LCM of the denominator, you will divide it of the denominator of 1/6 + 1/7 + 1/8 - 9 3/8.Then after you divide it,you will multiply it from the numerator.If you get the answer you can reduce it.
28/168 + 24/168 + 21/168 - 9 63/168 = 9 10/168 =
9 5/84