## Thinking Mathematically (6th Edition)

We begin with $3\times 3=9=2\times 4+1\times 1=21_{four}$ Record the 1, carry the 2 $\begin{array}{lll} & 2 & \\ & 2 & 3_{four}\\ \times & & 3_{four}\\ -- & -- & --\\ & & 1_{four} \end{array}$ Next $3\times2 +2=8=2\times4+0\times1=20_{four}$ Record this: $\begin{array}{lll} & 2 & \\ & 2 & 3_{four}\\ \times & & 3_{four}\\ -- & -- & --\\ 2 & 0 & 1_{four} \end{array}$ (the result is $201_{four})$