A pharmaceutical laboratory prepares a reagent. The ratio of medicine to water is (3/5). The weight of the medicine is 100 grams less than that of water. How many grams is the medicine? (answer in three ways)
药品实验室配制一种试剂，药与水的比是(3/5)，药比水的重量少100克，药有多少克？(用三种方法解答)
<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

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

<gadget id="calculator">100 / 2</gadget>
<output>50</output>

<gadget id="calculator">50 * 5</gadget>
<output>250</output>

<gadget id="calculator">1 / 250</gadget>
<output>1/250 = around 0.004</output>

<gadget id="calculator">(3/5) / (1/250)</gadget>
<output>150</output>

<result>150</result>