Answer:
Each of them need to pay to buy a whole pie together = $1.50
Explanation:
Unit rates defined as the rates are expressed as a quantity of 1, such as 7 feet per second or 9 miles per hour, they are called unit rates.
As per the statement: You sell pies at a farmers' market for $7.50 each.
⇒ Cost of each pie = $7.50
Also, five people want to share a pie by splitting the cost equally.
Number of people = 5
then, by definition of unit rate;
unit rate per people =

Therefore, $1.50 will each of them need to pay to buy a whole pie together.