amount = intitial amount (1/2)^(t/6), where t is hours and initial amount = 255
from 8:00 to 11:30 = 3.5 hours
from 8:00 to 4:00 pm = 8 hours
a) at 11:30, t = 3.5
amount of caffeine = 255(1/2)^(3.5/6) =170.192
b) at 4:00
amount = 255(.5)^(8/6) = 101.1968
she drinks another coffee containing 180 mg
so now she has 101.1968 + 180 or 281.1968 mg in her
half our later ,
amount left = 281.1968(.5)^(1/12) = appr 265.4 mg
The half-life caffeine in the human body is typically about 6 hours. If john drinks a large cafe mocha with an extra shot of expresso from a coffee shop at 8am (255mg caffeine), and then starts to feel drowsy around 4pm and drinks another large cafe mocha (no expresso, 180mg caffeine). Can anybody help me how to do this step by step? PLEASE
a)how much caffeine is in johns bloodstream at 11:30 am?
b) How much caffeine is in Mary's bloodstream at 4:30 pm?
1 answer
1 answer