At the school track meet, Dita ran 100 meters at a rate of 6.25 meters per second.

To find out how long it took Dita to finish the race, you can use the formula:

\[
\text{Time} = \frac{\text{Distance}}{\text{Rate}}
\]

In this case, the distance is 100 meters and the rate is 6.25 meters per second:

\[
\text{Time} = \frac{100 \text{ meters}}{6.25 \text{ meters/second}} = 16 \text{ seconds}
\]

So, the correct answer is:

**16 seconds**.