1. Before you took this course, you probably heard many stories about Statistics courses. Oftentimes
parents of students have had bad experiences with Statistics courses and pass on their anxieties to their
children. To test whether actually taking AP Statistics decreases students' anxieties about Statistics, an
AP Statistics instructor gave a test to rate student anxiety at the beginning and end of his course.
Anxiety levels were measured on a scale of 0-10. Here are the data for 16 randomly chosen students
from a class of 180 students:
paired
t
SU
Pre-course anxiety level
Post-course anxiety level
Difference (Post - Pre)
7 6 9 5
4 3 7 3
-3 -3 -2 -2
6 7
4 5
-2 -2
5
4
-1
7 6 4
6 5 3
-1 -1 -1
3
2
-1
2 1
2 1
0 0
3
3
0
4
4
0
2
3
1

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.