Question

Question 15
The value of ${249}^2–{248}^2$ is

A) $1^2$
B) $477$
C) $487$
​​​​​​​D) $497$

Answer 1

The answer is D.
${249}^2–{248}^2=(249+248)(249-248)$ [ using identity, $a^2-b^2=(a-b)(a+b)$]
$497\times 1=497$