Question

Find the square of $83$ without actual multiplication.

• A. $6880$
• B. $3881$
• C. $3889$
• D. $6889$

Answer 1

The correct option is D $6889$

Use the formula $(a+b{)}^2=a^2+2\cdot a\cdot b+b^2$ where $a=80$ and $b=3$,

$(80+3{)}^2={80}^2+2\cdot 80\cdot 3+3^2$

${83}^2=6400+480+9$

$=6889$

Hence, option $D$ is correct.