Math Problem Solver

$$55555 + 44444=99999$$

$$\begin{aligned} \mathtt{5}\mathtt{5}\mathtt{5}\mathtt{5}\mathtt{5}\\ \mathtt{+\phantom{0}}\mathtt{4}\mathtt{4}\mathtt{4}\mathtt{4}\mathtt{4}\\ \hline \mathtt{9}\mathtt{9}\mathtt{9}\mathtt{9}\mathtt{9} \end{aligned}$$

$9$ is the digit in the $10^{0}$ place. $5 \times 10^{0} + 4 \times 10^{0} = 9 \times 10^{0}$.

$9$ is the digit in the $10^{1}$ place. $5 \times 10^{1} + 4 \times 10^{1} = 9 \times 10^{1}$.

$9$ is the digit in the $10^{2}$ place. $5 \times 10^{2} + 4 \times 10^{2} = 9 \times 10^{2}$.

$9$ is the digit in the $10^{3}$ place. $5 \times 10^{3} + 4 \times 10^{3} = 9 \times 10^{3}$.

$9$ is the digit in the $10^{4}$ place. $5 \times 10^{4} + 4 \times 10^{4} = 9 \times 10^{4}$.