A, B, and C are in a 100-meter race. A reaches the finish line 20 meters faster than B, and A reaches the finish line 28 meters faster than C. If B and C are in a race, how much faster is B than C to finish the 100 meters?
甲、乙、丙三人在一百公尺比赛中，甲比乙快20公尺到终点，甲又比丙快28公尺到终点．如乙和丙比赛，问乙比丙快多少公尺跑完一百公尺﹖
<gadget id="calculator">100 - 20</gadget>
<output>80</output>

<gadget id="calculator">80 / 72</gadget>
<output>10/9 = around 1.111111</output>

<gadget id="calculator">1 / (10/9)</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">100 * (9/10)</gadget>
<output>90</output>

<gadget id="calculator">100 - 90</gadget>
<output>10</output>

<result>10</result>