Question

Evaluate ${\left(\frac{0.05}{0.25}+\frac{0.25}{0.05}\right)}^3$

• A. 143.9
• B. 140
• C. 140.608
• D. 139.4

Answer 1

The correct option is C 140.608

${\left(\frac{0.05}{0.25}+\frac{0.25}{0.05}\right)}^3$

$={\left(\frac{\frac{5}{100}}{\frac{25}{100}}+\frac{\frac{25}{100}}{\frac{5}{100}}\right)}^3$

$={\left(\frac{5}{25}+\frac{25}{5}\right)}^3$

$={\left(\frac{1}{5}+5\right)}^3$

$={(0.2+5)}^3={\left(5.2\right)}^3=5.2\times 5.2\times 5.2$

$=27.04\times 5.2=140.608$