Given that A:B=2:9, (1/(A))-(1/(B))=(1/54), find the value of A+B.
已知A：B=2：9，(1/(A))-(1/(B))=(1/54)，求A+B的值是多少．
<gadget id="calculator">9 - 2</gadget>
<output>7</output>

<gadget id="calculator">7 / 972</gadget>
<output>7/972 = around 0.007202</output>

<gadget id="calculator">(7/972) * 2</gadget>
<output>7/486 = around 0.014403</output>

<gadget id="calculator">(7/972) * 9</gadget>
<output>7/108 = around 0.064815</output>

<gadget id="calculator">(7/486) + (7/108)</gadget>
<output>77/972 = around 0.079218</output>

<result>77/972 = around 0.079218</result>