To transport a pile of gravel, first use a large truck with a load of 4 tons to transport once, and then use 5 similar small trucks to transport the rest exactly once. If the cut weight of the small truck is 75% of that of the large truck, how many tons of gravel are there in total?
运一堆砂石，先用1辆载重4吨的大卡车运1次后，剩下的用5辆同样的小卡车刚好1次运完．如果小卡车的裁重量是大卡车的75%，这堆砂石共有多少吨？
<gadget id="calculator">75 / 100</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">4 * (3/4) * 5</gadget>
<output>15</output>

<gadget id="calculator">15 + 4</gadget>
<output>19</output>

<result>19</result>