Two boards of the same length are nailed together to form a relatively long board. The length of the longer board is 45 cm. If the overlapping part nailed together in the middle is 5 cm long, what is the length of each of the two boards?
两块一样长的木板钉在一起，成了一块比较长的木板，这块较长木板长45厘米，如果中间钉在一起的重叠部分长5厘米，那么这两块木板各长多少厘米．
<gadget id="calculator">45 + 5</gadget>
<output>50</output>

<gadget id="calculator">50 / 2</gadget>
<output>25</output>

<result>25</result>