There are 48 students in a certain class, 18 of them are girls, how many girls are transferred later, girls are 40% of the whole class at this time.
某班有学生48人，其中女生有18人，后来又转来多少名女生，这时女生是全班人数的40%．
<gadget id="calculator">48 - 18</gadget>
<output>30</output>

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

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">30 / (3/5)</gadget>
<output>50</output>

<gadget id="calculator">50 - 48</gadget>
<output>2</output>

<result>2</result>