Let's continue the example. You bought at $101 at support of $100. Higher up, at $108, there's resistance: the price has already turned there twice. The target is $107.5, just below the ceiling. Don't get greedy over the last few cents: many people sell at the ceiling.
Now do the math, as in course 2. The risk is $2.5 to the stop, the profit is $6.5 to the target. The profit is more than two risks, so the trade is good. But if the ceiling were at $105, the profit would be less than two risks, and the trade would be worth skipping.