100 grams of salt water contains 40% salt, and after adding 10 grams of salt and 90 grams of water, what is the salt content at this time?
在100克盐水中含盐40%，再加入10克盐和90克水后，这时含盐率是多少
<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">100 * (2/5)</gadget>
<output>40</output>

<gadget id="calculator">40 + 10</gadget>
<output>50</output>

<gadget id="calculator">100 + 10 + 90</gadget>
<output>200</output>

<gadget id="calculator">50 / 200</gadget>
<output>1/4 = around 0.25</output>

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

<gadget id="calculator">(1/4) * 1</gadget>
<output>1/4 = around 0.25</output>

<result>1/4 = around 0.25</result>