Use the formula to find the distance traveled by car,
Speed = distance/time
You want distance so change the formula so that it's: Distance = speed x time.
Therefore,
D= 68 x 4.75 (I got 4.75 since it's 4 hours and 45 min. 45 min of 1 hour is 3/4. 3/4 is .75!!)
= 323 miles