Answer: A) 480
Step-by-step explanation:
The information that we have is:
Total number of students: 1200
25% are 8th grade
35% are 7th grade
the rest is 6th grade.
To find the percentage that corresponds to 6th grade, we substract 25% and 35% from 100%:
So 40% of the students are 6th graders.
Now to find how much students this is, we need to divide the total number od students by 100, and then multiply by 40:
the answer is A)480