Hello!
There are two parts to a fraction. The numerator (top part of a fraction) is how many of the denominator you have, and the denominator (bottom part of a fraction) is how many in total.
There are 8 students in total, and 6 of them are NOT blue shirts.
To find out how many students are wearing blue shirts, we must subtract the amount of students who aren't wearing blue from the total amount of students.
8 - 6 =
The denominator will remain the same, but the numerator will change from 6 to 2. The fraction looks like:
2/8
ANSWER
2/8 of the students are wearing blue shirts.