Final answer:
Dana assumed an equal split of the total cost among her friends.
Step-by-step explanation:
The assumption that Dana made to decide the amount each friend owes her is that she evenly split the total cost of snacks among her friends. Since Dana spent $14.50 and she has some friends who owe her, she divided the total cost by the number of friends to determine how much each friend owes. In this case, there are 5 friends (including Dana), so $14.50 divided by 5 equals $2.90.
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