Question

8 is 4% of a, 4 is 8% of b and $=\frac{b}{a}$. What is the value of $\frac{a-b}{a+b}?$

• A. $\frac{1}{4}$
• B. $\frac{5}{3}$
• C. $\frac{3}{5}$
• D. $\frac{1}{2}$

Answer 1

The correct option is C $\frac{3}{5}$

$8=\frac{4}{100}\times a\Rightarrow a=8\times \frac{100}{4}=200$
$4=\frac{8}{100}\times b\Rightarrow b=4\times \frac{100}{8}=50$
Hence, $c=\frac{200-50}{200+50}=\frac{150}{250}$
$c=\frac{3}{5}$