There are 22.8 tons of cement on the construction site, the weight of gravel is 1.5 times that of cement, and the weight of sand is only half of that of gravel. How many tons of sand are there on the construction site?
工地上有水泥22.8吨，石子的重量是水泥的1.5倍，沙子的重量只有石子的一半，工地上有沙子多少吨？
<gadget id="calculator">1.5 / 2</gadget>
<output>0.75</output>

<gadget id="calculator">22.8 * 0.75</gadget>
<output>17.1</output>

<result>17.1</result>