7.5*2.3+1.9*2.5．
7.5*2.3+1.9*2.5．
<gadget id="calculator">7.5 * 2.3</gadget>
<output>17.25</output>

<gadget id="calculator">1.9 * 2.5</gadget>
<output>4.75</output>

<gadget id="calculator">17.25 + 4.75</gadget>
<output>22</output>

<result>22</result>