10 tons of seawater can produce 0.85 tons of salt, how many tons of seawater are needed to produce 1.7 tons of salt?
10吨海水可以晒出0.85吨盐，要晒出1.7吨盐，需要多少吨海水．
<gadget id="calculator">0.85 / 10</gadget>
<output>0.085</output>

<gadget id="calculator">1.7 / 0.085</gadget>
<output>20</output>

<result>20</result>