1*99+2*98+3*97+...+49*51.
1*99+2*98+3*97+…+49*51．
<gadget id="calculator">2_500 * 49</gadget>
<output>122_500</output>

<gadget id="calculator">99 / 6</gadget>
<output>33/2 = around 16.5</output>

<gadget id="calculator">49 * 50 * (33/2)</gadget>
<output>40_425</output>

<gadget id="calculator">122_500 - 40_425</gadget>
<output>82_075</output>

<result>82_075</result>