First example:
Subtract the 8n on both sides to get the variable on one side of the equation. Do the same for the regular numbers. Then divide by -3.

This should be your final answer.
Second Example:
Do the same thing as explained in Example 1. Here's some work to help guide you.

That should be your final answer here.
Third Example:

Hope this helps and its understandable! Let me know if you still don't understand.
She has 52 card all together so she has a probability of drawing on the first draw 4 L's or R's because their are two sets of alphabet cards. So that is 4/52 or 1/13 to the lowest term. Second turn she only has 51 cards to draw from and still has 4 L's and R's so that would be 4/51 and on the third try she has only 50 cards left so that would be 4/50 or 2/25 to the lowest term. Now multiply all three factions 1/13 x 4/51 x 2/25 = 8/16575 meaning out of the three draws she has a probability of getting a L or R, 8 out of 16575 each draw.
Answer:
b)37.5
Step-by-step explanation:
the ratio 3:2 is the same as 1.5, so you multiply 1.5 & 25 to get 37.5 units