The difference between 2 times a number minus 1.7 is equal to 18.5, this number.
一个数的2倍减去1.7的差等于18.5，这个数．
<gadget id="calculator">18.5 + 1.7</gadget>
<output>20.2</output>

<gadget id="calculator">20.2 / 2</gadget>
<output>10.1</output>

<result>10.1</result>