Zamba has found a little black dress on sale for 50% off the original price of $239.99. She also has a coupon offering free shipping and additional 10% off of her entire online purchase. If she buys the dress and a pair of shoes costing $34.70, how much will she pay for her ensemble?

She will pay $139.23 (which is rounded up from $139.2255).
You take the price of the dress, and subtract it from 50 percent off, which gives you $119.995. You then add in the price of the shoes, which gets you to $154.695. You then subtract the 10% off from $154.695, which gets you $139.23 after it's rounded up.