Huang Mofei's weight (2/5) is equal to Chen Ningfeng's (2/3); Huang Mofei's weight (3/7) is 1.5kg lighter than Chen Ningfeng's (3/4). Find the sum of the weights of the two people.
黄莫非体重的(2/5)与陈宁风的(2/3)相等；黄莫非体重的(3/7)比陈宁风体重的(3/4)轻1.5kg．求两人体重的总和．
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

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

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

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

<gadget id="calculator">(3/5) * (3/4)</gadget>
<output>9/20 = around 0.45</output>

<gadget id="calculator">3 / 7</gadget>
<output>3/7 = around 0.428571</output>

<gadget id="calculator">(9/20) - (3/7)</gadget>
<output>3/140 = around 0.021429</output>

<gadget id="calculator">1.5 / (3/140)</gadget>
<output>70</output>

<gadget id="calculator">70 * (3/5)</gadget>
<output>42</output>

<gadget id="calculator">70 + 42</gadget>
<output>112</output>

<result>112</result>