help

Notice that $a^3 + b^3 + c^3 - 3abc = (a + b + c)(a^2 + b^2 + c^2 - (ab + bc +ca))$

The only missing info we need is the value of $a^2 + b^2 + c^2$.

Now, because $(a + b + c)^2 = a^2 + b^2 + c^2 + 2(ab + bc + ca)$, plugging in values gives $a^2 + b^2 + c^2 = 11^2 - 2(25) = 71$

You can plug in the values on your own.

so like what maxwong said we have a^2+b^2+c^2=71 and a^3 + b^3 + c^3 - 3abc = (a + b + c)(a^2 + b^2 + c^2 - (ab + bc +ca))  plug that in to get 11*(71-25) and that equals 506.

_{^{Credts: Maxwong for hints}}