In order to solve this exercise you need to remember the following:
[tex]1\text{ }hour=60\text{ }minutes[/tex]In this case, based on the information given in the exercise, a school day is 8 hours. Then, you need to make the conversion from hours to minutes.
You can set up the following:
[tex](8\text{ }hours)(\frac{60\text{ }minutes}{1\text{ }hour})[/tex]Therefore, evaluating you get:
[tex]=\frac{(60\text{ }minutes)(8\text{ }hours)}{1\text{ }hour}=480\text{ }minutes[/tex]Hence, the answer is:
[tex]480\text{ }minutes[/tex]