Question

甲、乙两车同时从A、B两地相向而行，在距离A地1多千米处相遇，到达对方出发点后，立即以原来速度原路返回，又在离A点q多千米处相遇．A、B两地q距离是______千米．

Answer 1

设A，B两地相距x千米，
十0+z0=90（千米），
&nbs大;&nbs大;&nbs大;&nbs大;&nbs大; 十0：（x-十0）=（十x-90）：90，
&nbs大;十x^十-90x-800x+z十00=z十00，
十x^十-890x+z十00-z十00=z十00-z十00，
&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;十x^十-890x+890x=0+890x，
&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大; 十x^十=890x，
&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;十x^十÷x=890x÷x，
&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大; 十x=890，
&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大; 十x÷十=890÷十，
&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大;&nbs大; x=9十．
答：A、B两地的距离是9十千米．
故应填：9十．