Edit MetaData
9 years, 2 months ago
8 years, 10 months ago
But Aaditya, how can we deduce that 238th digit is odd? from ur explanation it is clear that 237th digit is even. It says nothing abt 238th digit... correct me if I am wrong..!!
9 years, 2 months ago
$$340^{235}$$ has 235 zeroes => first odd digit of $$340^{235}$$ is the same as first odd digit of $$34^{235}$$
$$34^x$$ always has last digit as even.
$$34^{even}$$ always has ten's digit as odd.
$$34^{odd}$$ always has ten's digit as even.
In our case, 235 is odd. Hence $$34^{235}$$ has ten's digit even
Ten's digit of $$34^{234}$$ is the 237th digit from the right of $$340^{235}$$ => 237th digit is even. So, 238th digit is odd.
Detailed syllabus & Topic-wise Weightage
By proceeding you agree to create your account
Free CAT Syllabus PDF will be sent to your email address soon !!!