and B are two natural numbers not equal to zero, (1/(A))+(1/(B))=(8/15), then, A+B=how much.
A和B是两个不等于零的自然数，(1/(A))+(1/(B))=(8/15)，那么，A+B=多少．
<gadget id="calculator">3 + 5</gadget>
<output>8</output>

<result>8</result>