Find the value of \(\sqrt{{385}+\sqrt{{213} +\sqrt{{144}}}}\)

Given expression:

$\sqrt{385+\sqrt{213+\sqrt{144}}}$

First, solve the inner root:

$\sqrt{144} = 12$

So,

$\sqrt{385+\sqrt{213+12}}$

$= \sqrt{385+\sqrt{225}}$

$= \sqrt{385+15}$

$= \sqrt{400}$

$= 20$