Question

If $12:16$ and $21:p$ are proportional to one another, then find the value of $p$.

• A. $35$
• B. $20$
• C. $24$
• D. $28$

Answer 1

The correct option is D $28$

Equate the product of the extremes to the product of the means:
$\Rightarrow 12\times p=21\times 16$
$\Rightarrow 12p=336$
$\Rightarrow p=28$
Hence, the correct answer is option B.