You know of a relative who is addicted to pain killers. Due to his history, 2.3g of Tylenol per day is dangerous. He takes 200 mg scored Tylenol tablets every six hours. For each six hour period (he takes the same number of tablets every six hours), how many scored tablets can the relative take without the amount being dangerous

Answer: So, your relative takes N tablets each 6 hours. a day has 24 hours, and 24/6 = 4, so he takes N tablets 4 times per day, so he takes 4*N tablets.

each tablet has 200mg, and 2.3 g (or 2300 mg) is toxic.

this means that 4*N*200mg must be less than 2300, if we are seeking for the maximum N possible, then:

4*N*200mg = 2300mg

4*N = 2300/200 = 11.5

N = 11.5/4 = 2.87

if you round up this number, you will end up taking more than 2.3g of tylenol per day, this implies that N must be equal to 2.

So your relative needs to take maximum 2 tablets per day.