The speed ratio of A and B is 9:10. A and B are walking toward each other from two places at the same time. When they meet, they are 5 kilometers away from the finish line. After meeting, they continue to move forward. When B arrives at A’s starting point, How many miles is A from B's starting point?
甲、乙两人的速度比是9：10，甲、乙两人同时从两地相向而行，相遇时离终点5千米，相遇后两人继续前进，当乙到达甲的出发地时，甲离乙的出发地有多少千米？
<gadget id="calculator">5 * 2</gadget>
<output>10</output>

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

<gadget id="calculator">1 - (9/10)</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">10 / (1/10)</gadget>
<output>100</output>

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

<gadget id="calculator">100 + 90</gadget>
<output>190</output>

<gadget id="calculator">190 * (1/10)</gadget>
<output>19</output>

<result>19</result>