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Numerical Ability
Number System
remainder of 2^47/47
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- ans 2
a^p-a is divisible by p when p is prime - 11 years agoHelpfull: Yes(9) No(0)
- answers is= 2
- 11 years agoHelpfull: Yes(6) No(3)
- ANS WILL BE=18
- 11 years agoHelpfull: Yes(5) No(13)
- ans is 2
it is because 2^23 leaves remainder 1 when divided by 47
so we can express 2^23 as 47x+1
so 2^46= (47x+1)^2 = (47x)^2 + 2*47x + 1
and 2*47 = 2*2^46=2*(47x)^2 + 2*2*47x + 2
we see that first two terms are divisible by 47 but last term i.e. 2 is not ..
so the remainder is 2
- 11 years agoHelpfull: Yes(5) No(2)
- mistake earlier
2^47/47 =(2^6)^7*(2^5)/47=((47+17)^7*(2^5))/47
=(17)^7*32/47=17*((17^2)^3)*32/47=17*((282+7)^3)*32/47 as 282 is divisible by 47 so
17*(7)^3*32/47=186592/47=2 hence 2 - 11 years agoHelpfull: Yes(4) No(3)
- lets start
2^47/47 =(2^6)*(2^5)/47=((47+17)^7*(2^5))/47
=(17)^7*32/47=17*((17^2)^3)*32/47=17*((282+7)^3)*32/47 as 282 is divisible by 47 so
17*(7)^3*32/47=186592/47=2 hence 2 is and uph had to do a lot :) thanks bfr - 11 years agoHelpfull: Yes(3) No(0)
- answers is= 24
- 11 years agoHelpfull: Yes(2) No(2)
- 2mod47=2
2^2mod47=4
2^4mod47=(2^2)*(2^2)mod47=4*4mod47=16
2^8mod47=(2^4)*(2^4)mod47=16*16mod47=21
2^16mod47=(2^8)*(2^8)mod47=21*21mod47=18
2^32mod47=(2^16)*(2^16)mod47=18*18mod47=42
2^47mod47=(2^32)*(2^8)*(2^4)*(2^2)*2mod47=42*21*16*4*2mod47=2
ANS=2 - 9 years agoHelpfull: Yes(2) No(0)
- 2^47/47=3*10^12
- 11 years agoHelpfull: Yes(0) No(3)
- Pls explain it clearly and crctly
- 9 years agoHelpfull: Yes(0) No(0)
- 2^47/47 =2
- 9 years agoHelpfull: Yes(0) No(0)
- Apply fermat's little theorem
a^(p-1) is congruent to 1 (mod p)
here a = 2, p = 47
Thus, 2^46 yields remainder 1,
So by property of congruence we can say
2^46 * 2 yields remainder 1 * 2. Answer is 2 - 6 years agoHelpfull: Yes(0) No(0)
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