14
You need to find all the people who read more than three hours. More than three hours would mean people who read more than 4, 5, or 6 hours. Since the number of people who read 4 hours is 6 dots and 5 hours are 3 dots, we add them together.
6+3
= 9
Since the number of people who read 6 hours is 5, we also add that.
9+5
= 14