Question

Certain can of soda contains 60 milligrams of caffeine. The caffeine is

eliminated from the body at a rate of 15% per hour. What is the half-life of the
caffeine? That is, how many hours does it take for half of the caffeine to eliminated
from the body?

Answer 1

3.33 hours

Explanation:

you have a total of 60mg, it is asked how much hours it takes to remove half the caffeine which is 30mg

1 hour removes 15%, 15% of 60 is 9g

(15/100×60) = 9

now it removes only 9g in an hour, we have to find out how long (hours) it'll take to remove 30g

30÷9= 3.33 hours