<human>:  Mark has a really bad headache. He takes 2 Tylenol tablets of 500 mg each and he does every 4 hours for 12 hours. How many grams of Tylenol does he end up taking?
<bot>: How many doses does he take? ** He takes 12/4=<<12/4=3>>3 doses
How many mg is each dose? ** Each dose is 500*2=<<500*2=1000>>1000 mg
How many mg does he take? ** So he takes 3*1000=<<3*1000=3000>>3000 mg
How many grams of Tylenol does he end up taking? ** So he takes 3000/1000=<<3000/1000=3>>3 grams of Tylenol
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