Two trains, A and B, depart from the two cities at the same time and meet after 5 hours. Train A travels 90 kilometers per hour, and train B is 10% slower than train A per hour. How far is the distance between the two cities?
甲、乙两列火车同时从两城相对开出，5小时后相遇，甲车每小时行90千米，乙车每小时比甲车慢10%，两城相距多远？
<gadget id="calculator">10 / 100</gadget>
<output>1/10 = around 0.1</output>

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

<gadget id="calculator">90 * (9/10)</gadget>
<output>81</output>

<gadget id="calculator">90 + 81</gadget>
<output>171</output>

<gadget id="calculator">171 * 5</gadget>
<output>855</output>

<result>855</result>