In a 1000-meter race, it is known that when A reaches the finish line, B is 50 meters away from the finish line;
1000米赛跑，已知甲到达终点时，乙离终点50米；乙到达终点时，丙离终点100米，那么甲到达终点时，丙离终点多少米．
<gadget id="calculator">1_000 - 50</gadget>
<output>950</output>

<gadget id="calculator">950 / 1_000</gadget>
<output>19/20 = around 0.95</output>

<gadget id="calculator">1_000 - 100</gadget>
<output>900</output>

<gadget id="calculator">900 / 1_000</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">(19/20) * (9/10)</gadget>
<output>171/200 = around 0.855</output>

<gadget id="calculator">1 - (171/200)</gadget>
<output>29/200 = around 0.145</output>

<gadget id="calculator">1_000 * (29/200)</gadget>
<output>145</output>

<result>145</result>