In the pond last year, 45 frogs were sick. After improving the environment, the disease rate of the frogs has been reduced by 60% this year. How many frogs are sick this year?
池塘中去年有45只青蛙生病，改善环境后，今年青蛙的民病率降低了60%，今年有几只青蛙生病？
<gadget id="calculator">60 / 100</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">1 - (3/5)</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">45 * (2/5)</gadget>
<output>18</output>

<result>18</result>