Math CentralQuandaries & Queries


Social Security numbers are in the form ###-##-####, where each symbol
represents a number 0-9, how many are possible with this format? Will we ever
run out of Social Security numbers?

(This is one question with two parts, I saw some examples but I am still confused
because if there are 1 million possibilities then how have we been able to issue out
numbers to over 280 million US citizens?) (For the second part a yes or no answer is sufficient)

Hi Tish,

I think you have some confusion with a million and a billion. I suggest you look at Billions and more!

Also go to the Quandaries and Queries section of Math Central and search in the quick search window for the term social security. One of the facts you will find there is that not every number that meets your template above is a valid social security number.


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