Question
$113 \times 87$
✓
Answer
Here, we will use the identity $(a-b)(a+b)=a^2-b^2$
Let us consider the following expression:
$113 \times 87$
$\because \frac{113+87}{2}=\frac{200}{2}=100$, therefore, we will write the above product as:
$113 \times 87$
$=(100+13)(100-13)$
$=(100)^2-(13)^2$
$=10000-169$
$=9831$
Thus, the answer is 9831
Let us consider the following expression:
$113 \times 87$
$\because \frac{113+87}{2}=\frac{200}{2}=100$, therefore, we will write the above product as:
$113 \times 87$
$=(100+13)(100-13)$
$=(100)^2-(13)^2$
$=10000-169$
$=9831$
Thus, the answer is 9831
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