Answer:
To find the unit price of bananas, we need to divide the total price by the number of bananas.
Unit price = Total price / Number of bananas
In this case, the total price is $3.20 and the number of bananas is 4.
Unit price = $3.20 / 4
Unit price = $0.80
So the unit price of bananas in this grocery store is $0.80 per banana.