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what is the remainder when 1!+2!+3!+...+199! is divided by 21?
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- each term from 7! to 199! is completely divisible by 21
so (1!+2!+...+6!)/21 gives the required remainder
=(1+2+6+24+120+720)/21=873/21 which gives remainder 12
ans is 12 - 11 years agoHelpfull: Yes(46) No(0)
- 12 Ans.
because 7! are divided by 21.so 8!to 199!are also divided by 21.
only we check 1!+2!....6!=873/21 gives remainder 12.
- 11 years agoHelpfull: Yes(7) No(0)
- (1!+2!+3!+4!+5!+6!)/21= rem..12
rest of terms are divisble by 21 - 11 years agoHelpfull: Yes(3) No(1)
- bhaag milkha bhaag
- 11 years agoHelpfull: Yes(2) No(1)
- each term from 7! to 199! is completely divisible by 21
so (1!+2!+...+6!)/21 gives the required remainder
=(1+2+6+24+120+720)/6=873/6 which gives remainder 3
ans is 3 - 11 years agoHelpfull: Yes(1) No(4)
- ans is 12
- 11 years agoHelpfull: Yes(1) No(0)
- 12
it is divisible 4m 7! onwards
so remainder of 1!+2!+3!+4!+5!+6! is the answer
- 11 years agoHelpfull: Yes(0) No(0)
- from 6! onwards all the terms will be divisible by 21.
as we know 21=7*3.
7!,8!,......199! all have 7and3 so , it will be completely divisible.
1!+2!......6!= 873%21 = 12.
so the remainder will be 12. - 11 years agoHelpfull: Yes(0) No(0)
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