Final answer:
Dining in is slightly cheaper than eating out according to the mean cost of ingredients at the grocery store and the mean price of a comparable restaurant meal.
Step-by-step explanation:
To determine whether eating out or dining in is cheaper, we can compare the mean cost of buying ingredients at the grocery store and cooking a meal with the mean price of a comparable restaurant meal. According to the given information, the mean cost of a flank steak, broccoli, and rice from the grocery store is $13.04. On the other hand, a sample of 100 neighborhood restaurants showed a mean price of $12.75 for a comparable meal. Therefore, based on these averages, dining in is slightly cheaper than eating out.