Answer: Based on the given information, we can analyze the distances run by each person:
Gabby ran a shorter distance than Gina.
Gina did not run a longer distance than Bert.
Justin ran a shorter distance than Gina but a longer distance than Gabby.
From statement 1, we know that Gina ran a longer distance than Gabby. From statement 3, Justin ran a shorter distance than Gina. Combining these two statements, we can conclude that Gabby ran a shorter distance than Justin.
Since statement 2 states that Gina did not run a longer distance than Bert, we can infer that Bert ran a longer distance than Gina. Therefore, Gabby ran a shorter distance than Bert.
In conclusion, Gabby ran a shorter distance than Bert.