There are 14 consecutive natural numbers, and the sum of the first 7 consecutive natural numbers is 105. So, what is the sum of these 14 consecutive natural numbers?
有14个连续自然数，前7个连续自然数的和是105．那么，这14个连续自然数的和是多少．
<gadget id="calculator">105 * 2</gadget>
<output>210</output>

<gadget id="calculator">1 + 13</gadget>
<output>14</output>

<gadget id="calculator">7 / 2</gadget>
<output>7/2 = around 3.5</output>

<gadget id="calculator">14 * (7/2)</gadget>
<output>49</output>

<gadget id="calculator">210 + 49</gadget>
<output>259</output>

<result>259</result>