the line plot shows how many siblings each student has. how many more students have only one sibling than at least 3 siblings
        x                   Â
        x     x             Â
        x     x              Â
    x    x     x     x          Â
    x    x     x     x    x       Â
    x    x     x     x    x   Â
<----l-------l--------l-------l-------l--->