Final answer:
Jeff's total bill is $15.95. After applying a 20% discount, he needs to pay $12.76. If he pays with a $20.00 bill, he will receive $7.24 in change.
Step-by-step explanation:
To calculate the total cost, we add up the cost of each item. Jeff buys 3 boxes of cereal at $2.99 each, so the total cost of cereal is $2.99 x 3 = $8.97. He buys 1 gallon of milk for $4.98 and 4 bananas for $0.50 each, so the total cost of milk is $4.98 and the total cost of bananas is $0.50 x 4 = $2.00. Adding all these costs together, Jeff's total bill comes to $8.97 + $4.98 + $2.00 = $15.95.
Next, we calculate the discount Jeff gets with his 20% off coupon. To find the discount amount, we multiply the total bill by 20%: $15.95 x 0.20 = $3.19. Subtracting this discount from the total bill gives us the final amount Jeff needs to pay: $15.95 - $3.19 = $12.76.
Finally, we calculate how much change Jeff will get. He pays with a $20.00 bill, so his change will be $20.00 - $12.76 = $7.24.