Conditional probability
Given that a person has attended college,
we want to find the probability that the person has a Moderate political ideology:
We have that the probability is given by:

We have that the number of voters that have a Moderate ideology that have gone to college is 20.
moderate and college = 20
The number of voters that have gone to college is 17 + 20 + 17 = 54
college = 54
Then,

simplifying the answer:

Answer: 10/27