Student 1 and 3.

Move the negative into the brackets,
positive becomes negative while two negatives make a positive.
The answer to this equation is 7
The total number of students in the four classes is 100 students.
<h3>How to compute the value?</h3>
From the information, the numbers of students in the four sixth-grade classes at Northside School are 26, 19, 34, and 21.
Therefore, the total number of students will be:
= 26 + 19 + 34 + 21
= 100
Therefore there are 100 students.
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