Uncle Wang drove from place A to place B at 60 kilometers per hour for 6 hours. When returning, due to the task, the speed was accelerated, and it only took 4 hours to return to Jiadi. What was the speed when returning?
王叔叔开车从甲地到乙地，每小时行60千米，行了6小时．返回时由于有任务，加快了速度，只用了4小时就回到了甲地，返回时的速度是多少？
<gadget id="calculator">6 / 4</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">60 * (3/2)</gadget>
<output>90</output>

<result>90</result>