A and B represent different numbers, AB and BA are two-digit numbers, AB*BA=403, then A+B=how much.
A、B表示不同的数字，AB和BA都是两位数，AB*BA=403，那么A+B=多少．
<gadget id="calculator">1 * 3</gadget>
<output>3</output>

<gadget id="calculator">1 + 3</gadget>
<output>4</output>

<result>4</result>