The younger brother drove the donkey to pull another cart, and then the younger brother sent the donkey back to help the older brother pull the cart, and then he pulled the cart and walked the last part of the road. It is known that the speed of the two brothers pulling the cart is the same, the donkey pulls the cart or walks. The speed is three times that of a man pulling a cart, and the two brothers arrived at the same time, so where should the younger brother drive the donkey back?
弟弟赶毛驴拉另一辆车，然后在中途弟弟让毛驴返回去帮哥哥拉车，自个儿拉着车行走完最后一段路，已知兄弟俩人的拉车速度相同，毛驴拉车或行走的速度为人拉车的速度的3倍，兄弟俩同时到达，那么弟弟应该在哪儿将毛驴赶回去？
<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<result>2/3 = around 0.666667</result>