Question: its with regards to part c ive computed everything...

It’s with regards to part c). I’ve computed everything and using the empirical formula, I’ve found that 68% of females spend 2-16 hours, 95% spend 0-38hours and 99.7% spend 0-50 hours. How do I go about comparing it to the actual result and know if it’s a good approximation of the actual results? If yes or no, what could the reasons be for that?