3.
30 divided by 10 equals 3
To get the probability of selecting a person who is a
democrat and is favour to the issue, let us first calculate for the portions in
each party who is favour on the issue.
p (rep & favour) = 0.4 * 0.3 = 0.12
p (dem & favour) = 0.6 * 0.7 = 0.42
Therefore the total portions who are favour is:
p (favour) = 0.12 + 0.42 = 0.54
Hence the probability is:
P (dem & favour) = 0.42 / 0.54 = 0.7778 = 0.78
Therefore there is about 78% probability that the person
selected who is favour to the issue is a democrat.
6/10 can be simplified but we don't need to worry about it right now. We only need to worry about simplifying 20/100:
20/100 → 10/50 → 5/25 → 1/5
Find common denominators
1/5 → 2/10
6/10
Now, add.
6/10 + 2/10 = 8/10
Therefore, the equation is true.
Best of Luck!
