Answer: the equation is 4t = 3.60
The cost of 1 pound of banana is $0.9
Explanation:
Let t represent the cost of 1 pound of banana in dollars.
Gavin paid for 4 pounds of bananas. This means that the total cost of 4 pounds of banana will be 4× t = $4t
He gave a $10 bill to the seller and he was given back $6.40. This means that the actual cost of 4 pounds of banana would be
10 - 6.40 = $3.60
Therefore,
4t = 3.60
t = 3.60/4 = $0.9