Three consecutive natural numbers, the first number is (7/8) of the third number, what is the second natural number.
三个连续的自然数，第一个数是第三个数的(7/8)，求第二个自然数是多少．
<gadget id="calculator">7 / 8</gadget>
<output>7/8 = around 0.875</output>

<gadget id="calculator">1 - (7/8)</gadget>
<output>1/8 = around 0.125</output>

<gadget id="calculator">2 / (1/8)</gadget>
<output>16</output>

<gadget id="calculator">16 - 1</gadget>
<output>15</output>

<result>15</result>