Question

From the grocery store you need to purchase 1/2 lb cheese, 3 lbs sliced ham, 2 loaves of bread, 4 bags of potato chips, and 1 container of salsa. You have a coupon for $4.00 off if your purchase totals more than $15.00 or 10% off if the total is more than $20.00. The food sales tax is 3%. Which coupon offer will save you the most money?

Answer 1

we would need to know how much the items cost

but once you've summed up the prices, simply try applying the first coupon (subtract 4 dollars if the total is > $15). multiply by 1.03 to account for the 3% tax.

then start over and apply the second coupon (if the total is >$20, then multiply by 0.9 which will take 10% off the total. multiply by 1.03 to account for the 3% tax.

then see which total ends up being smaller to see which coupon saved more money.