car full of goods drives from A to B at 52 kilometers per hour and arrives in 3.5 hours. When I came back, because the car was empty, I only traveled for 2.6 hours. How many kilometers per hour did I travel on average when I came back?
一辆装满货物的汽车从甲地开往乙地，每小时行52千米，3.5小时到达．回来时由于空车，只行了2.6小时，回来时平均每小时行多少千米？
<gadget id="calculator">3.5 / 2.6</gadget>
<output>1.346154</output>

<gadget id="calculator">52 * 1.346154</gadget>
<output>70.000008</output>

<result>70.000008</result>