What is the 26th digit?
N is a 50 digit number( in the decimal scale). All digits except the 26th digit(from the left) are 1. If N is divisible by 13, find the 26th digit.
Re: What is the 26th digit?
Hint:
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Tahmid Hasan
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Re: What is the 26th digit?
notice that 111111 is divisible by 13.so111111....111111(24) is div by 13
and then 111111....1111(24)XY11111....1111(24)is div by 13[X and Y r the 25th n 26th digits]
here X=1 ,so the only choice for Y to b div by 13 is 3.
(someone help me to hide this)
and then 111111....1111(24)XY11111....1111(24)is div by 13[X and Y r the 25th n 26th digits]
here X=1 ,so the only choice for Y to b div by 13 is 3.
(someone help me to hide this)
বড় ভালবাসি তোমায়,মা
Re: What is the 26th digit?
We can divide a number by 13 when the sum of the digit of the number will divide by 13.So,the ans. is 3.
Re: What is the 26th digit?
Sorry,it isn't true,try infinite counter-examples like $26$
One one thing is neutral in the universe, that is $0$.