If you took 800mg of aspirin tablet at 12:00pm and another 800mg tablet at 2pm, how many milligrams of aspirin are still in your system at 3pm? Aspirin has a t1/2 of 1 hour. Don't you dare put a link. I have a very specific set of skills >.>
(Chemistry is unfortunately not one of them though, so please help me ^-^)

100mg are in your system at 3pm

Explanation:

Half-life is the time necessary to decrease the initial amount of a substance in the half.

At 12:00pm, the amount of aspirin is 800mg

As half-life is 1h,

at 1:00pm, the amount of aspirin is 800mg/2 = 400mg

At 2:00pm, 400mg/2 = 200mg

At 3:00pm, 200mg/2 =

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