Huahua, Yingying and Lele used (1/2), (2/3) and (3/4) of their pocket money to buy a math competition reference book. If Huahua had 15 yuan in pocket money left at this time, how much money would Yingying and Lele have in total?
华华，英英和乐乐三个小朋友分别用各自的零花钱的(1/2)，(2/3)和(3/4)去买了一本数学竞赛参考书．如果此时华华剩下15元零花钱，那么英英和乐乐共还剩下多少元钱．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 - (1/2)</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">15 / (1/2)</gadget>
<output>30</output>

<gadget id="calculator">30 - 15</gadget>
<output>15</output>

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

<gadget id="calculator">15 / (2/3)</gadget>
<output>45/2 = around 22.5</output>

<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">15 / (3/4)</gadget>
<output>20</output>

<gadget id="calculator">15 * 2</gadget>
<output>30</output>

<gadget id="calculator">20 - 30</gadget>
<output>-10</output>

<gadget id="calculator">(45/2) + (-10)</gadget>
<output>25/2 = around 12.5</output>

<result>25/2 = around 12.5</result>