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what is the remainder when 100! is divided by 97^2?
1.582 2.8148 3.1261 4.8827
Read Solution (Total 8)
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- first understand dis
(6*10*55)/9
remainder of this is 6. there r two ways to calculate this
1--- 6*10*55 ie 3300 mod 9 = 6
2--- 6 mod 9 =6
10 mod 9 =1
55 mod 9=1
thn multiply all the rem n u get the ans ie 6
in case of 97^2
100*99*98*97*96! / 97^2
97 will b cancel out
100*99*98*96 ! / 97
nw find out remainder individually
100 % 97 =3
99 % 97 =2
98 % 97=1
and acc to wilson theorem
if p is a prime no thn (p-1)! mod p =-1
here 97 is a prime no so
96!% 97 = -1 or 96
so multiply all the rem
3 * 2*1* 96 mod 97 = 576 mod 97 = 91
nw multiply 91 with 97 so we get
91*97= 8827 - 12 years agoHelpfull: Yes(28) No(4)
- Wilson Theorem ???
How does dat come by ??
and how to apply it ??
Wilson Theorem is for Prime No. and 96 is NOT a prime ...
Please elaborate a bit more !!!
Thx !! - 12 years agoHelpfull: Yes(10) No(0)
- 100*99*98*97*96! mod 97^2 (applied wilson theorm for 96!)
cancel out 97 from numerator and denominator
3*2*1*96 mod 97
576 mod 97
91 mod 97
mos rem is 97*91=8827 - 12 years agoHelpfull: Yes(8) No(9)
- 8827 is the remainder when 100! is divided by 97^2.
- 12 years agoHelpfull: Yes(4) No(1)
- @kajal sharma
plzz xplain, why u multiplied by 97 in last line? i.e 91*97 :/ - 11 years agoHelpfull: Yes(3) No(0)
- Please give the Explanation !!!!
- 12 years agoHelpfull: Yes(2) No(1)
- 97 is a prime number.
- 12 years agoHelpfull: Yes(2) No(1)
- @smita pls help us to understand the solution
explain why u did this
3*2*1*96 mod 97 - 12 years agoHelpfull: Yes(0) No(2)
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