Answer:
40 7th grade students.
Step-by-step explanation:
Ok so first we know the total equals 100. In order to divide the number of 6th graders and 7th graders equally, we add 15 and 10 which equals 25. Now, 100 divided 25 equals 4. Boom! We multiply 15 by 4 and that equals 60. This means there are 60 6th graders. We multiply 10 by 4 which means there are 40 7th graders. Now to check if we did it all right we add 60 and 40 which equals 100 STUDENTS IN ALL. This means we did it right. So it asked us for the amount of 7th graders which is 40! Hope this helps.