The sum of the four numbers A, B, C, and D is 23.4, and it is known that the number A is 2.5 times, the number B is subtracted by 1, the number C is added by 4, and the (1/2) of the number D is equal to each other, then A, B What is the product of the four numbers , C, and D?
数A，B，C，D四个数的和是23.4，又已知数A的2.5倍，数B减1，数C加4，数D的(1/2)彼此相等，则A，B，C，D这四个数的积是多少．
<gadget id="calculator">4 * 2.5</gadget>
<output>10</output>

<gadget id="calculator">23.4 * 2.5</gadget>
<output>58.5</output>

<gadget id="calculator">58.5 - 2.5</gadget>
<output>56</output>

<gadget id="calculator">10 + 56</gadget>
<output>66</output>

<gadget id="calculator">2 * 2.5</gadget>
<output>5</output>

<gadget id="calculator">1 + 2.5 + 2.5 + 5</gadget>
<output>11</output>

<gadget id="calculator">66 / 11 / 2.5</gadget>
<output>2.4</output>

<gadget id="calculator">66 / 11</gadget>
<output>6</output>

<gadget id="calculator">6 + 1</gadget>
<output>7</output>

<gadget id="calculator">6 - 4</gadget>
<output>2</output>

<gadget id="calculator">2.4 * 7 * 2 * 2 * 6</gadget>
<output>403.2</output>

<result>403.2</result>