Answer:
Tammy was overcharged by $1.20
Explanations:
Price of an apple at the cash register = 50 cents = $0.5
Price of an orange at the cash register = 50 cents = $0.5
Tammy bought a dozen apples and 8 oranges
Cost of a dozen of apples = 12 x $0.5 = $6
Cost of 8 oranges = 8 x $0.5 = $4
Total amount paid by Tammy = $6 + $4 = $10
Prices displayed at the grocery:
Cost of apples = 3 for $1.00
Cost of oranges = 5 for $3.00
Cost of a dozen apples at 3 for $1.00 = (1/3 x 12) = $4
Cost of 8 oranges at 5 for $3.00 = (3/5 x 8) = $4.8
Total cost = $4 + $4.8 = $8.8
Tammy paid $10 instead of $8.8
Difference in the actual cost and the amount paid by Tammy = $10 - $8.8
Difference in the actual cost and the amount paid by Tammy = $1.2
Tammy was overcharged $1.20