The histogram shows the results of a survey asking students how many video games they currently own.


A histogram titled Video Game Ownership has Number of video games on the x-axis and number of students on the y-axis. 4 students have 0 to 9 games; 9, 10 to 19; 10, 20 to 29; 3, 30 to 39; 1, 40 to 49.


How many observations were used to create the display?