(9³-3³):3²

First, calculate the terms inside the parenthesis:

\(9^3 = 9 \times 9 \times 9 = 729\)

\(3^3 = 3 \times 3 \times 3 = 27\)

Now subtract the smaller cubed number from the larger one:

\(9^3 - 3^3 = 729 - 27 = 702\)

Now divide the result by \(3^2\):

\(3^2 = 3 \times 3 = 9\)

So the final calculation is:

\( \frac{702}{9} = 78\)

Therefore, the result of \((9^3 - 3^3) : 3^2\) is 78.