Answer: 600 mg in 36 hours.
Step-by-step explanation:
1. Divide 36 by 9, so you know how many times the infant has to take the medicine. 36/9=4
2. Multiply 150x4 because the infant has to take 150 mg, each dosage. 150x4=600.
3. Your final answer is 600 mg. (You did not need the infant's weight in this problem. So, that's why it was not worked in.)
Hope this helps. :)