Answer:
There are 250 students in the 6th grade.
Explanation:
[] Let us do "number of students" over the percentage. We will use x as the total number of students in the 6th grade.
-> 35% and 100% can be divided by 100 to become decimals
Set up a proportion:

Cross multiply:
85 = 0.34x
Divide both sides by 0.34:
250 = x
Reflexive property:
x = 250
Have a nice day!
I hope this is what you are looking for, but if not - comment! I will edit and update my answer accordingly.
- Heather