Answer: An hour and a half.
Explanation:
1. We know that it takes 2 hours to make 12 necklaces so in order to get how many necklaces she can make in an hour we must divide.
2. 12/2=6. It takes Kerion one hour to make 6 beaded necklaces.
3. Now, half of 6 is 3. So, we add 6+3 to get your nine necklaces.
4. Since we know one hour makes 6 necklaces, to make 3 necklaces would take half an hour.
5. Add the hour and a half, and you get 90 minutes.
Hopes this helps :)