Question 1182542
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In web-page


https://www.quora.com/What-is-the-first-non-zero-digit-in-50-factorial-50-How-did-you-get-the-answer-without-a-calculator#:~:text=The%20answer%20is%202%2C%20see,compute%20the%20factorization%20of%2050!


you can find different solutions for any taste.



The &nbsp;&nbsp;<U>ANSWER</U> &nbsp;&nbsp;is &nbsp;&nbsp;2.




Even better form solution, &nbsp;with examples, &nbsp;including the case 50!, &nbsp;is under this link


https://www.justquant.com/numbertheory/how-to-find-last-non-zero-digit-in-a-factorial/



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<pre>
Also, a good idea is to present 50! as the product of five groups of numbers


    50! = (1*2*3*4*. . .*9*10) * (11*12*13*. . .*19*20) * (21*22*23*. . .*29*30) * (31*32*33*. . .*39*40) * (41*42*43*. . .*49*50)


It is clear that the last non-zero digit of 50! is the product of last non-zero digits of all five groups.


Regarding 1st group, 10! = 3628800;  the last non-zero digit is 8.


Regarding 2nd group, (11*12*13*. . . *18*19*20) = 670442572800;  the last non-zero digit is 8.


Regarding 3rd group, (21*22*23*. . . *28*29*30) = 109027350432000;  the last non-zero digit is 2.


Regarding 4th group, (31*32*33*. . . *38*39*40) = 3075990524006400;  the last non-zero digit is 4.


Regarding 5th group, (41*42*43*. . . *48*49*50) = 37276043023296000;  the last non-zero digit is 6.


Now,  the product of the last non-zero digits in these groups is  8*8*2*4*6 = 3072;


so, my DIRECT EMPIRICAL EXPERIMENT  <U>C O N F I R M S</U>  that the last non-zero digit in the number 50!  is  {{{highlight(highlight(2))}}}.
</pre>

Thanks to my &nbsp;MS &nbsp;EXCEL, &nbsp;making these boring calculations for me easy, &nbsp;fast and with no errors &nbsp;(&nbsp;!&nbsp;)