The number of boys in a class is 2/3 of the number of girls, and after a boy is transferred, the boys are girls (7/10), how many people are there in the class now?
某班男生人数是女生人数的(2/3)，后来转来1名男生后，男生是女生的(7/10)，现在全班有多少人？
<gadget id="calculator">7 / 10</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">(7/10) - (2/3)</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">1 / (1/30)</gadget>
<output>30</output>

<gadget id="calculator">30 * (7/10)</gadget>
<output>21</output>

<gadget id="calculator">30 + 21</gadget>
<output>51</output>

<result>51</result>