A kind of concrete on a construction site is made by mixing cement, yellow sand, and stones in a ratio of 2:3:5. If there are 8 tons of cement, how many tons of such concrete can be prepared.
建筑工地上一种混凝土是用水泥、黄沙、石子按2：3：5混合而成的．如果有水泥8吨，则能配制这样的混凝土多少吨．
<gadget id="calculator">8 / 2</gadget>
<output>4</output>

<gadget id="calculator">2 + 3 + 5</gadget>
<output>10</output>

<gadget id="calculator">4 * 10</gadget>
<output>40</output>

<result>40</result>