so first make sure thtat the bottom number is the same so
7 and 3 and 2
multily them together and get 42
so multtiply 3/7 by 6/6 or 1=18/42
multiply 2/3 by 14/14=28/42
multply 1/2 by 21/21=21/42
18/42+28/42+21/42=(18+28+21)/42=67/42
simplify
1 and 25/42 miles