1*3+2*4+3*5+...+9*11.
1*3+2*4+3*5+…+9*11．
<gadget id="calculator">1 + 9</gadget>
<output>10</output>

<gadget id="calculator">9 / 2</gadget>
<output>9/2 = around 4.5</output>

<gadget id="calculator">3 * 10 * (9/2)</gadget>
<output>135</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(1/3) * 8 * 9 * 10</gadget>
<output>240</output>

<gadget id="calculator">135 + 240</gadget>
<output>375</output>

<result>375</result>