Question

$\frac{8.73\times 8.73\times 8.73+4.27\times 4.27\times 4.27}{8.73\times 8.73-8.73\times 4.27+4.27\times 4.27}=$

• A. $11$
• B. $12$
• C. $13$
• D. $10$

Answer 1

The correct option is C $13$

Given exp = $\frac{{\left(8.73\right)}^3+{\left(4.27\right)}^3}{{\left(8.73\right)}^2-8.73\times 4.27+{\left(4.27\right)}^2}$
$=\frac{(8.73+4.27)[{\left(8.73\right)}^2-8.73\times 4.27+{\left(4.27\right)}^2]}{[{\left(8.73\right)}^2-8.73\times 4.27+{\left(4.27\right)}^2]}$ ...$[\because a^3+b^3=(a+b)(a^2-ab+b^2)]$

$=(8.73+4.27)=13$