Question

find the third proportinal to 9 and 12.​

Answer 1

$\huge\underline{\underline{\texttt{{Question:}}}}$

$\small\bold\green{find \: the \: third \: proportinal \: to \: 9 \: and \: 12}$

$\huge\underline{\underline{\texttt{{Solution:}}}}$

$\small\bold{consider \: their \: ratios \: be \: 9:12:x}$

$\implies\small\bold\orange{ \frac{9}{12} = \frac{12}{x} }$

$\small\bold{by \: cross \: multiplication}$

$\small\bold{9x = 12 \times 12}$

$\small\bold{9x = 144}$

$\sf\: x = \cancel\frac{144}{9} = 16$

$\implies \: \small\bold\red{x = 16}$

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Answer 2

The third proportional to 9 and 12 is 16.