Stacy, Oliver, and Jivesh each plan to put a certain amount of money into their savings accounts that earn simple interest of 6% per year. Stacy puts $550 more than Jivesh, and Oliver puts in 2 times as much as Jivesh. After a year, the amount in Stacy's account is 2 times the sum of $212 and the amount in Oliver's account.

Mrs. julien’s and mrs. castillejo’s classes are selling cookie dough for a school fundraiser. customers can buy packages of macadamia nut chip cookie dough and packages of triple chocolate cookie dough. mrs. julien’s class sold 25 packages of macadamia nut chip cookie dough and 30 packages of triple chocolate cookie dough for a total of $221.25. mrs. castillejo’s class sold 5 packages of macadamia nut chip cookie dough and 45 packages of triple chocolate cookie dough for a total of $191.25. (a) write the system of equations that model the problem. be sure to explain which equation represents which situation. (b) find the cost of each type of cookie. show your work. (c) explain which method you used to solve the system and why you chose that method.