Question

Solve each of the following Cryptarithm:
$$\begin{gathered} \begin{array}{ccc}& A& 1\\ +& 1& B\end{array} \\ \overline{\begin{array}{ccc}& B& 0\end{array}} \end{gathered}$$

Answer 1

$$\begin{gathered} \mathrm{If}1+\mathrm{B}=0 \\ \mathrm{Surely},\mathrm{B}=9 \\ \mathrm{If}1+\mathrm{A}+1=9 \\ \mathrm{Surely},\mathrm{A}=7 \end{gathered}$$