Exercise 1.2.18 A school has three clubs and each stu- dent is required to belong to exactly one club. One year the students switched club membership as follows: 4 Club A. A remain in A, switch to B,...

Extracted text: Exercise 1.2.18 A school has three clubs and each stu- dent is required to belong to exactly one club. One year the students switched club membership as follows: 4 Club A. A remain in A, switch to B, switch to C. 5 • 10 10 Club B. 6 remain in B, 3 switch to A, o switch to C. 10 2 • 10 10 Club C. remain in C, 2 switch to A, 3 switch to B. 6 10 10 If the fraction of the student population in each club is unchanged, find each of these fractions.