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Find the last non-zero digit of 30^2345
Read Solution (Total 4)
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- 3^1=3;
3^2=9;
3^3=27;
3^4=81;
3^5=243; so it is a power cycle of 4, (9,7,1,3 will be repeating ...) so
2345/4 gives you 1; so 3^1= 3 so 3 is the remainder.. - 10 years agoHelpfull: Yes(13) No(1)
- 30^2345=(3*10)^2345=3^2345*10^2345
so 30^2345 has 2345 zeroes,the last non-zero digit of 30^2345 will be same as unit digit of 3^2345
3^2345=3^(4*586+1)=> 3^1=3
last non-zero digit of 30^2345= 3 - 10 years agoHelpfull: Yes(11) No(1)
- 3
eg: 30^5
30x30=900
900x30=27000
27000x30=810000
810000x30=24300000
similarly at 2345th time , it wud b 3.. coz 2345 s a multiple of 5
- 10 years agoHelpfull: Yes(5) No(1)
- Ans : 3
30^2345 = 3^2345 * 10^2345
3^1=3 3^2=9 3^3=27 3^4=81 then it will repeat!
So 2345%4 would give a remainder of 1 and hence the remainder is 3! - 9 years agoHelpfull: Yes(0) No(0)
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