Answer:
Cara:108
Step-by-step explanation:
John: x number of cards
Cara: 12 times x number of cards(she has 12 times more cards than John)
Cara+John=117 cards

Cara has 12×9 cards, so she has 108 cards.
Hope this was helpful :)
39.66 is the answer to the problem
This is an algebra expression. What we do is write it down in simplest form.
1. Write down equation
= 17 - 3 x n
= 3 x n + (-17)
I hope this answer helped. Have a great day everyone!