A doctor's prescription calls for 1/5 of an ounce of a particular ingredient for every 20 pounds of body weight. How many ounces of the ingredient would be needed by somebody weighing 175 pounds?

1 Answer

1.75 ounces of medicine

Explanation:

Let's divide how much the patient weighs, 175 pounds, by 20 pounds, or the amount that decides the amount of medicine a patient receives:

#175/20=8.75#

So we need 8.75 units of the medicine. Each unit is #1/5=0.2# of an ounce. This means that we need:

#8.75xx0.2=1.75# ounces of medicine