Question

Find $p$, if $\frac{21}{105}=\frac{p}{p+3}$.

• A. $\frac{4}{3}$
• B. $\frac{3}{4}$
• C. $\frac{-3}{4}$
• D. None of the above

Answer 1

Answer: (B)

$\frac{3}{4}$

Given, $\frac{21}{105}=\frac{p}{p+3}$

$⟹\frac{1}{5}=\frac{p}{p+3}$ ...[On simplifying]

$⟹5p=p+3$ …[Cross-multiplying the denominators].

Transposing $p$ terms to one side, we get,

$⟹5p-p=3$

$⟹4p=3$

$\therefore p=\frac{3}{4}$.

Hence, option $B$ is correct.