Mom brings 100 yuan to the street to buy things. The ratio of the money used to the rest of the money is 3:5. How much money did my mother spend?
妈妈带100元上街买东西，用去的钱与余下的钱的比是3：5，妈妈用去了多少元．
<gadget id="calculator">3 + 5</gadget>
<output>8</output>

<gadget id="calculator">3 / 8</gadget>
<output>3/8 = around 0.375</output>

<gadget id="calculator">100 * (3/8)</gadget>
<output>75/2 = around 37.5</output>

<result>75/2 = around 37.5</result>