Question

How many digits are possible in the square of a 'n' digit number?

• A. $2n+1$
• B. $2n-1$
• C. $n^2$
• D. 2n

Answer 1

Answer: (B), (C), (D)

The correct options are
B $2n-1$
C $n^2$
D 2n

Let us consider 1st number as $1$

No. of digit : $1$

Square : $1^2=1$

No. of digit in square = $1$

satisfying options (B) and (C)

Now let us consider 2nd number as $4$

No. of digit : $1$

Square : $4^2=16$

No. of digit in square = $2$

satisfying options (D)

If we take 3rd number as $25$

No. of digit : $2$

Square : ${25}^2=625$

No. of digit in square = $3$

satisfying options (B)