Math Problem Solver

$$40 - 4=36$$

$$\begin{aligned} \overset{\mathtt{{\scriptscriptstyle 3}}}{\cancel{\mathtt{4}}}\overset{\mathtt{{\scriptscriptstyle 10}}}{\cancel{\mathtt{0}}}\\ \mathtt{-\phantom{0}}\phantom{0}\mathtt{4}\\ \hline \mathtt{3}\mathtt{6} \end{aligned}$$

Borrow $10^{1}$, resulting in $3$ in the $10^{1}$ place, and $10$ in the $10^{0}$ place.

$6$ is the digit in the $10^{0}$ place. $10 \times 10^{0} - 4 \times 10^{0} = 6 \times 10^{0}$.

$3$ is the digit in the $10^{1}$ place. $3 \times 10^{1} - 0 \times 10^{1} = 3 \times 10^{1}$.