Question

Mitchell is a big coffee fan, so he always takes care of coffee brewing at the office. Normally he uses 100 grams of Robusta coffee to prepare 10 cups of coffee. His friend brings him a packet of Arabica coffee and tells him that he should use 20% more than usual when brewing Arabica coffee. How many grams of coffee should he use to make a

15-cup pot of Arabica coffee?

Answer 1

Since Mitchell will be making 50% more coffee than usual, we need to multiply 100 grams of coffee by 1.5, giving us 150 grams of coffee. But because we need to use 20% more coffee grounds, multiply 150 by .2 and add that amount to 150. So the answer is 180 grams of coffee.