A school keeps track of the percentage of scholars who pack lunch versus buy lunch. On Monday, 80% of scholars packed lunch. On Tuesday, 70% of the scholars who packed lunch do so again, and 50% of those who bought lunch on Monday pack lunch on Tuesday. Assume all scholars either pack lunch or buy lunch. Find the percent change in the number of scholars who bought lunch from Monday to Tuesday, and indicate whether this was an increase or decrease.

(50 ) 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.