Scotch

the denominator of a fraction exceeds the numerator by 7, if the numerator is increased by 3, and the denominator is increased by 5, the resulting fraction equals 1/2. Find the original fraction.

Justin recently drove to visit his parents who live 480 miles away. On his way there his speed was 20 miles per hour faster than on his way home (he ran into bad weather). If Justin spent a total of 20 hours driving. Find the two rates.