Answer: They need to drive 154 miles before they stop for the night.
Explanation:
Given: Total distance for trip = 440 miles
Halfway distance =
Let x be the distance they need to drive to reach halfway from the current position.
Since, they already drove 66 miles, so
x+66 = 220
⇒ x = 220-66
⇒ x = 154 miles
Hence, they need to drive 154 miles before they stop for the night.