Answer:
$278.40
Step-by-step explanation:
Note: "...an additional 10% off any shoe item, once the first discount has been applied." (emphasis added).
Note that the customer is buying 3 pairs of shoes for $120 each: 120 x 3 = $360
The first discount is the 20% discount (on every single item), the second discount is the 10% discount coupon of of any item (which signifies one item only).
Solve for the first discount:
$360 x 0.20 = $72
$360 - 72 = $288.
Next, divide $288 by 3 (to get the individual prices of the shoes:
$288/3 = $96.
The customer then uses a birthday coupon for one of the shoes, which gives an additional 10% off.
$96 x 0.10 = 9.6
$96 - 9.6 = $86.4
Remember, the other two shoes still cost $96 each. Add the price together:
$96 + $96 + $86.4 = $278.40
$278.40 will be the total.
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