Question

Find $x$ if $5:4::125:x$

• A. 100
• B. 50
• C. 120
• D. 101

Answer 1

The correct option is A

100

$5:4::125:x\Rightarrow \frac{5}{4}=\frac{125}{x}$

$\Rightarrow \frac{4}{5}=\frac{x}{125}$

$\Rightarrow x=\frac{125\times 4}{5}=25\times 4$

$\Rightarrow x=100$