Question

Find out the third proportional to 16 and 36

Answer 1

Let the third proportional to 16 and 36 is $x$.
Then, $16:36::36:x$

$\Rightarrow 16\times x=36\times 36$

$\Rightarrow x=\frac{36\times 36}{16}=81$
$\therefore$ Third proportional to 16 and 36 is 81