If there are 4 fewer boys in a class than 5/9 of the whole class, and 6 more girls than 40% of the whole class, then how many fewer boys are there than girls in this class?
某班男生比全班人数的(5/9)少4人，女生比全班人数的40%多6人，那么该班男生比女生少多少人．
<gadget id="calculator">6 - 4</gadget>
<output>2</output>

<gadget id="calculator">5 / 9</gadget>
<output>5/9 = around 0.555556</output>

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

<gadget id="calculator">1 - (5/9) - (2/5)</gadget>
<output>2/45 = around 0.044444</output>

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

<gadget id="calculator">45 * (5/9)</gadget>
<output>25</output>

<gadget id="calculator">25 - 4</gadget>
<output>21</output>

<gadget id="calculator">45 - 21 - 21</gadget>
<output>3</output>

<result>3</result>