Question

How many zeros will the square of $7000000$ have?

• A. $6$
• B. $8$
• C. $10$
• D. $12$

Answer 1

The correct option is D $12$

If a number ends with $n$ zeros, then its square will end with $2n$ zeros.
Since, $7000000$ ends with $6$ zeros, its square will end with $12(=2\times 6)$ zeros.

${7000000}^2=7000000\times 7000000$
$=49000000000000$