You can round each number to the nearest half
12 3/8 = 12 1/2
6 7/8 = 7
Now, you have: 12 ½ × 7
Since you have a mixed number, change it to a decimal to make it easier.
12 ½ = 12.5
12.5 × 7 = 87.5
The product of 12 3/8 and 6 7/8 is about 87 1/2 = 87.5
~Aamira~
Hope this helped :)