grammar - Periods in quotes and how to end the sentence the quote lies in

If I am quoting someone in my writing, and I end their quote with a period, and the end of the quote is also the end of my sentence. How do I properly end the sentence? An example of this is in my last question:

For example, "The file is not updat(e)able.".

Here is another example:

The boss said, "If you don't get your work in by tomorrow, you're
fired.".

Is that how you properly end the sentence, or should I leave one of the periods out? If the latter, could you explain why?

Answer

For standard American English, omit the period at the end of the sentence and leave the one inside the quotation.