When you see a sign in your favorite store saying that everything is 30% off, can you do the math to figure out what that means? Are you good at keeping track of how much things cost—while remembering how much money you actually have in your wallet? What about sales tax? Do you remember to add that on to your total costs when you're deciding if you have enough money to buy a pair of jeans? Shopping Math can help you do all this and more!