Solve the series of equations. 2 times a number is 6.5 more than 18.5, what is this number?
列方程求解．一个数的2倍比18.5多6.5，这个数是多少？
<gadget id="calculator">6.5 + 18.5</gadget>
<output>25</output>

<gadget id="calculator">25 / 2</gadget>
<output>25/2 = around 12.5</output>

<result>25/2 = around 12.5</result>