Nick opens a bank account with $50. Each week after, he deposits $15. In how many weeks will he have

Nick opens a bank account with $50. Each week after, he deposits $15. In how many weeks will he have saved $500

Start with remaining balance:
500 - 50 = 450

Now figure out how many weeks, at 15 per week, to get 450
450/15 = 30 weeks