Answer:
We obtain the average velocity instead of the instantaneus velocity.
Step-by-step explanation:
The problem with calculating speed in this way is that an average speed is being calculated and not an instantaneous speed at a given point.
![V_(average) =(x)/(t) \\where:\\x = distance\\t = interval of time](https://img.qammunity.org/2021/formulas/physics/middle-school/g9penbua5p16wvtj0im14u83b788m6ufbd.png)
To calculate the instantaneous speed, a very small space interval must be measured at a given time.