Algebra
posted by Bob on .
Hot Java Coffee Company adverties their decaffeinated coffee as 97% caffeine free as compared to their regular caffeinated coffee. If a cup of coffee is 8 ounces, how many ounces of decaffeinated coffee would you have to drink to get the equivalent amount of caffeine found in two cups of regular coffee?

The decaf coffee contains 3 units of caffeine per cup (100 minus 97). The regular coffee contains 100 units of caffeine per cup. Two cups of regular coffee contains 200 units, so you would have to drink 200/3 = 66.666 cups of decaf. 66.666*8 = 533.333 ounces

3x + 2y =2

3x + 2y = 2

x4y=8

Jenny received a gift card for a coffee store. She used it in buying some coffee that cost per pound. After buying the coffee, she had left on her card. How many pounds of coffee did she buy?