Billy has already run 6 miles because 1 plus 1 plus 1 plus 1 plus 1 plus plus 1 equals 6
Tiffany has already run 7 miles because 2 plus 2 plus 2 plus 1/3 plus 1/3 plus 1/3 equals <<2+2+2+1/3+1/3+1/3=7>>7
Billy has to run 1 mile to tie Tiffany because 7 minus 6 equals 1.
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