Hey!
Let's take the first question, we have to turn the equation

into a formula that correctly solves for F. First, let's switch the sides of the equation.

Divide both sides by 5/9. We are doing this to undo the multiplication.


Add 32 to both sides.


We have successfully gotten the formula to get F.
For the second question, we could use a graph for this. Since we want to reach the 400, then the inequality should reach that too. We should be careful though, since the profit will depend on the number of books you will sell, then the profit should be on the y-axis, and the number of books should be on the x-axis. The answer would be <span>
50 ≤ x ≤ 100
</span>
For the third question, we can also infer that the 35 students that did not like skating should represent the 25% of the students. So, we could set up a proportion.

We would then multiply, and then divide.

Now we know that the number of students who liked skating was 105 students.
-TetraFish