Answer:
15g ointment at 50%
Step-by-step explanation:
Data
We need to prepare 50g of an ointment with 15% of zinc oxide (O15)
with a Lote 1 =50% zinc oxide
50% ⇒ 100g oinment 50g are zinc oxide, so
50g ointment 15% ⇒ 50g oinment*15zo/100g ointment = 7.5g zo, also
g ointment =100g ointment*7.5g zo*/50g zo = 15g ointment