(At the doctor's office)
Nurse: How many cups of caffeine do you drink per day?
Me: Remember, tea has only about a third as much caffeine as coffee. Those coffee drinkers that have "only" one cup a day are already at 3 cups of tea, caffeine wise. Therefore, my answer is 1/3rd to 2/3rds.
Nurse: (Rolls eyes, probably just writes down "1") Ok.