To transport a pile of sand at one time, four vehicles with a load of 4.5 tons and six vehicles with a load of 8.5 tons are required. How many tons is this pile of sand?
运一堆沙，一次运完，需要载重4.5吨的汽车4辆载重8.5吨的汽车6辆，这堆沙有多少吨？
<gadget id="calculator">4.5 * 4</gadget>
<output>18</output>

<gadget id="calculator">8.5 * 6</gadget>
<output>51</output>

<gadget id="calculator">18 + 51</gadget>
<output>69</output>

<result>69</result>