approximately 2/3 of all students are not wearing braces because 165 (the difference of 250-85) /250 is 0.66
This may help:There are

gallons of lemonade.
Two friends share the lemonade.
What fraction of the lemonade does each friend receive?
To solve you do kcf or keep change flip.
You keep

and change division to multiplication.
Then

is changed to

<span>The answer would be </span>

Hope That Helps!
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