In order to find the answer to this question, you would need to find the Greatest Common Factor of 16 and 12 which would be 4 because 4 is the greatest amount that you can divide both 12 and 16 by. So the soonest both ships will leave together again will be in 4 days.
Answer:
25 necklaces
Step-by-step explanation:
each necklace brings $16 profit (20-4=16)
400÷ 16= 25
so, at 25 necklaces, there will be enough profit to break even after paying for the advertising.