What is the sum of 90+91+92+93+…+99
90+91+92+93+…+99的和为多少
<gadget id="calculator">90 + 99</gadget>
<output>189</output>

<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">189 * 5</gadget>
<output>945</output>

<result>945</result>