how long does it take for each cargo reach its destination

Question

Two cars travel the same distance. The first car travels at a rate of 42 miles per hour and reaches its destination in t hours. The second car travels at a rate of 58 miles per hour and reaches its destination 4 hours earlier than the first car. How long does it take for each car to reach its destination?

Answer 1

since the first car covers the distance D in t hour, the second car will cover the same distance in t-4 hours

so distance is: for first car  42t   for second car  58(t-4)

so it will be  42t=58(t-4)   42t=58t-232  42t-58t=-232.  -16t=-232   t=-232/-16 = 14.5 hours

so the first car runs for 14.5 hours to cover the distance and the second one runs for 14.5-4=10.5 hours

The distance is: 42*14.5 = 58*10.5 = 609 miles