What is the result of dividing the sum of 5.2 and 4.7 by their difference?
5.2与4.7的和除以它们的差，结果是多少．
<gadget id="calculator">5.2 + 4.7</gadget>
<output>9.9</output>

<gadget id="calculator">5.2 - 4.7</gadget>
<output>0.5</output>

<gadget id="calculator">9.9 / 0.5</gadget>
<output>19.8</output>

<result>19.8</result>