Here is the question. It's probably very simple and I just can't figure it out:

A statistics professor plans classes so carefully that the lengths of her classes are uniformly distributed between 50.0 and 52.0 minutes. Find the probability that the class runs less than 50.25 minutes.

Does this have something to do with a z-score? I know probability=percent (at least thats what my teacher says) but I'm not sure how to work this one...and it seems like it should be so simple.

Thank you!!