Answer: 47.5 miles per hour
Explanation:
We know that ,

Given : The distance to the friend’s house is 276.45 miles. It takes the family 5.82 hours to complete the trip.
i.e. Distance = 276.45 miles
Time = 5.82 hours
Then, the rate(speed) for the family’s trip in miles per hour will be :-

Hence, the rate for the family’s trip = 47.5 miles per hour