Devin spent some of his birthday money at a game store. Now, he has \$ 7$7 less than his sister, Kaylee. Type an expression to represent the amount of money Devin has now. ​Let K represent the amount of money Kaylee has.

​ Enter your answer in the box.

part b .Kaylee has \$ 15, how much money does Devin have now?

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.