The value of

Question:

The value of $(249)^{2}-(248)^{2}$ is

(a) $1^{2}$

(b) 477

(c) 487

(d) 497

Solution:

$(249)^{2}-(248)^{2}$

We know

$a^{2}-b^{2}=(a+b)(a-b)$

So,

$(249)^{2}-(248)^{2}=(249-248)(249+248)=497$

Hence, the correct answer is option (d).