*Given
Total number of students - 54
Fraction of students going to lunch first - 2/3
Fraction of students going to the exhibit first - 1/3
*Solution
1. Since the students are grouped into 3, the total number of students must be divided into 3 to determine the number of students in each of the 3 groups.
54/3 = 18
Thus, there are 18 students per group.
2. Two-thirds (2/3) of the total number of students will go to lunch first. Since the total number of students have already been divided into 3 groups, this simply means that 2 of the 3 groups will go to lunch first. Since each group has 18 students, 2 groups would have,
18*2 = 36
Thus, 36 students will go to lunch first.