Answer:
To solve this problem, we can use the formula distance = rate x time.
For the first part of the trip on the highway, Jennifer travels at an average rate of 54 1/2 miles per hour for 3 hours, so the distance she covers is:
distance = rate x time
distance = (54 1/2) x 3
distance = (109/2) x 3
distance = 327/2
distance = 163.5 miles
For the second part of the trip on the smaller route, Jennifer travels at an average rate of 34.25 miles per hour for 3 hours, so the distance she covers is:
distance = rate x time
distance = 34.25 x 3
distance = 102.75 miles
The total distance Jennifer has driven after 6 hours is the sum of the distances she covered on both parts of the trip:
total distance = 163.5 + 102.75
total distance = 266.25 miles
Therefore, the answer is (A) 266.25 miles.