The time required by A and B to walk the same distance is 5 hours and 3 hours respectively. Now the two of them have to walk 10 kilometers and ask to arrive at the same time. Who will start first? How many kilometers to go first?
甲、乙两人走同一段路需要的时间分别是5小时和3小时．现在他们两人要走10千米的路，要求同时到达，谁先出发？先走多少千米的路？
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">10 / (1/5)</gadget>
<output>50</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">10 / (1/3)</gadget>
<output>30</output>

<gadget id="calculator">50 - 30</gadget>
<output>20</output>

<gadget id="calculator">(1/5) * 20</gadget>
<output>4</output>

<result>4</result>