Answer:
24 Jars
Step-by-step explanation:
Do 16/2, which gives you eight for every necklace. Then do 192/8 which would give you 24. So, she would need 24 jars for 192 necklaces.
Simple...
you have:

To make this into an improper fraction-->>
1.) Multiply whole number by denominator
2.)Add the number you got plus the numerator
3.) Use the original denominator to finish your improper fraction
Example:

4*9=36
36+4=40

Thus, your answer.