Question

Caffeine in the blood stream has a half life of 5 hours. A venti

sized coffee from Starbucks has 415 mg of caffeine. How much
caffeine would be left (to the nearest whole number) behind in
your body 22 hours after drinking a venti coffee?​

Answer 1

20 mg

Explanation:

The amount remaining is:

A = P (½)^(t / T)

where P is the original amount,

t is time,

and T is the half life.

A = 415 (½)^(22/5)

A ≈ 20