Answer
$18r^3$
Work Step by Step
We start with the given expression: $6r^2\times3r$
We rearrange and regroup the factors by like terms: $(6\times3)(r^2r)$
We multiply the constants: $18r^2r$
To multiply powers with the same base, we add the exponents: $18r^{2+1}=18r^3$