For this case we have the following equation:

We apply distributive property on the left side of the equation:

We simplify the left side of the equation:

Different signs are subtracted and the major sign is placed.

On the right side we must take into account that:

So:

We add x to both sides of the equation:

We subtract 2 from both sides of the equation:

We multiply by 3 on both sides of the equation:

We divide by 8 on both sides of the equation:

Thus, the solution of the equation is:

Answer:

40 students prefer vanilla. To get this answer you need to multiply 200 times 0.2 because you are trying to find 20%
The Federal Reserve sets an minimum rate to for lending to other banks.