A certain standardized test's math scores have a bell-shaped distribution with a mean of 520 and a standard deviation of 119. What percentage of standardized test scores is between 163 and 877? I...

A certain standardized test's math scores have a bell-shaped distribution with a mean of 520 and a standard deviation of 119.

What percentage of standardized test scores is between 163 and877?

I can't figure out how to solve this problem for my stats homework and how the standard deviation works.