The sum of 10 consecutive even numbers is 3.5 times the sum of 10 consecutive odd numbers starting from 1. What is the largest even number?
10个连续偶数的和是从1开始的10个连续奇数和的3.5倍，其中最大的偶数是多少．
<gadget id="calculator">1 + 19</gadget>
<output>20</output>

<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">20 * 5</gadget>
<output>100</output>

<gadget id="calculator">100 * 3.5</gadget>
<output>350</output>

<gadget id="calculator">350 / 10</gadget>
<output>35</output>

<gadget id="calculator">35 * 2</gadget>
<output>70</output>

<gadget id="calculator">10 * 2</gadget>
<output>20</output>

<gadget id="calculator">20 - 2</gadget>
<output>18</output>

<gadget id="calculator">70 + 18</gadget>
<output>88</output>

<gadget id="calculator">88 / 2</gadget>
<output>44</output>

<result>44</result>