simplify: 15/16 - 7/8 x 5/7

multiply first:

7/8 x 5/7 = 35/56

they need a common denominator to subtract, which would be 112.

15/16 x 7/7 = 105/112

35/56 x 2/2 = 70/112

105/112 - 70/112 = 35/112

that simplifies to 5/16.