Answer:
121 people
Explanation:
When counting the number of people who liked cotton candy or popcorn, we add 140 and 126, meaning we get 266 people liked one or the other.
However, we are counting the people who liked both twice, so we subtract 87 from this to get 179.
Now we know how many people liked cotton candy OR popcorn OR both, we can just subtract it from the total to see how many people liked neither.
300 - 179 = 121 people who like neither popcorn nor cotton candy