First, the denominator is the amount of subjects (for example colors). Say the question is find the probability of red. Say there is 4 blue dots, 9 red dots, 2 yellow dots, and 3 orange dots. The denominator would be 18 (the amount of dots). The numerator would be 9 because that is how many dots that were red are there. The answer would be 9/18 = 1/2. I hope his helps :)
Answer:
1st question: 5 (you already answered this one but I still included it)
2nd question: 21
3rd question: 8
4th question: 7
5th question: 12
6th question: 36
7th question: 15
8th question: 80