There are 11 male waiters at the airport, which is 1 less than the number of female waiters (2/5). How many female waiters are there at the airport?
机场有男服务员11人，比女服务员的(2/5)少1人，机场有女服务员多少人？
<gadget id="calculator">11 + 1</gadget>
<output>12</output>

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

<gadget id="calculator">12 / (2/5)</gadget>
<output>30</output>

<result>30</result>