Answer:
16 runners
Explanation:
The graph shows on the y-axis the number of runners for each bar height. On the x-axis, it shows the time intervals (that the runners ran in this scenario). The question wants to know how many UNDER 13 minutes, which means from 7:00-12:59.
To find the NUMBER, we have to add the amounts on each bar BEFORE 13 minutes, which totals 16 (2 + 6 + 8).
Hope I helped!