There are three classes in the sixth grade of our school. In one activity for the poor students, the donation of class one was the sum of the donations of classes two and three (2/3); the donation of class two was the donation of classes one and three. The sum of the numbers (2/5), it is known that the donation of the third class is 18 yuan less than that of the first class, how much is the total donation of the three classes?
我校六年级有三个班，有一次为贫困生献爱心活动中，一班的捐款是二、三班的捐款数之和的(2/3)；二班的捐款数是一、三班捐款数之和的(2/5)，已知三班捐款数比一班少捐18元，问三个班共捐多少钱？
<gadget id="calculator">2 + 3</gadget>
<output>5</output>

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

<gadget id="calculator">2 + 5</gadget>
<output>7</output>

<gadget id="calculator">2 / 7</gadget>
<output>2/7 = around 0.285714</output>

<gadget id="calculator">1 - (2/5) - (2/7)</gadget>
<output>11/35 = around 0.314286</output>

<gadget id="calculator">(2/5) - (11/35)</gadget>
<output>3/35 = around 0.085714</output>

<gadget id="calculator">18 / (3/35)</gadget>
<output>210</output>

<result>210</result>