If x+1.5=7.5, then 5.1x=how much.
如果x+1.5=7.5，那么5.1x=多少．
<gadget id="calculator">7.5 - 1.5</gadget>
<output>6</output>

<gadget id="calculator">5.1 * 6</gadget>
<output>30.6</output>

<result>30.6</result>