If a bottle contains 16.9 fluid ounces and a person drank 80% of it how many fluid ounces did that person drink?

For this problem, we need to find 80 of the total liquid. We can set the equation up like this, "what number = 80% of the total fluid ounces?" Let's fill in what we know and solve for what we don't! Okay, we don't know the "what number" part of the equation, so let's fill that in with the letter x. We can change 80% to 0.8, since that is its decimal form. Okay so far, we have x = 0.8*total fluid ounces. All we have to do now is find the total number of fluid ounces, which we see is 16.9. Alright. Our final equation is x = 0.8 * 16.9. now, solve for "x" to find your answer! Just multiply 16.9 by 0.8 to get

16.9*0.8 = 13.52 fluid ounces