Question 24
In the multiplication problem below $A,$ $B,$ $C,$ $D$ are different digits. What is $A+B?$ $$
\begin{array}{cccc}& A & B & A\\ \times & & C & D\\ \hline C & D & C & D\\ \end{array}
$$
\begin{array}{cccc}& A & B & A\\ \times & & C & D\\ \hline C & D & C & D\\ \end{array}
$$