Find unit digit
Probability
Level
2
Find the last two digits (tens and units) of
1! + 2! + 3! + 4! ...............................2015!
Problem is not original.
24
14
22
13
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1 solution
When we consider given expression from 10! we get unit digits as 00. so the uni digit of given expression is 01+02+06+24+120+720+5040+.....20+......80=13