Answer: 12%
Explanation:
Since the ointment contains 12 gms of active ingredient with 100 gms of ointment base, the concentration of the active ingredient in the ointment will be:
= Content if active ingredient/Content of ointment base × 100
= 12/100 × 100.
= 12%
Therefore, the the concentration of the active ingredient in the ointment is 12%.
