What is the concentration of salt water obtained by mixing three kinds of salt water with a concentration of 20%, 30% and 40% in a ratio of 2:3:5?
把浓度为20%、30%、40%的三种盐水按2：3：5的比例混合在一起，得到的盐水浓度为多少
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

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

<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">(3/10) * 3</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

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

<gadget id="calculator">(2/5) + (9/10) + 2</gadget>
<output>33/10 = around 3.3</output>

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

<gadget id="calculator">(33/10) / 10</gadget>
<output>33/100 = around 0.33</output>

<gadget id="calculator">100 / 100</gadget>
<output>1</output>

<gadget id="calculator">(33/100) * 1</gadget>
<output>33/100 = around 0.33</output>

<result>33/100 = around 0.33</result>