Answer: It should take her 13 weeks.
Step-by-step explanation:
If the bike costs $326 and she already has $131, we can subtract 131 from 326. 326-131=195. Now we know that Jennifer needs $195 dollars. Next, since she adds $15 each week, divide 195 by 15. 195/15= 13. It should take Jennifer 13 weeks so save up for her bike.