If 0.5x-10.9=78.1, then 1.2x+12.8=how much.
如果0.5x-10.9=78.1，那么1.2x+12.8=多少．
<gadget id="calculator">78.1 + 10.9</gadget>
<output>89</output>

<gadget id="calculator">89 / 0.5</gadget>
<output>178</output>

<gadget id="calculator">178 * 1.2</gadget>
<output>213.6</output>

<gadget id="calculator">213.6 + 12.8</gadget>
<output>226.4</output>

<result>226.4</result>