Let $T = (a,b,c)$ be a triangle with sides $a$, $b$, and $c$, and area $\triangle$. Denote by $T' = (a',b',c')$ the triangle whose sides are the altitudes of $T$ (i.e., $a' = h_a$, $b' = h_b$, $c' = h_c$) and denote its area by $\triangle'$. Similarly, let $T'' = (a'',b'',c'')$ be the triangle formed from the altitudes of $T'$, and denote its area by $\triangle''$. Given that $\triangle' = 30$ and $\triangle'' = 20$, find $\triangle$.

Let's think step by step and output the final answer within \boxed{}.
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