Two ships depart from Shanghai and Wuhan at the same time. The speeds of the two ships are 36 km/h and 27 km/h respectively. After 20 hours, they meet. How many kilometers is the waterway from Shanghai to Wuhan?
两艘轮船同时从上海和武汉相对开出，两船的速度分别是36千米/时、27千米/时，经过20小时相遇．上海到武汉的航道长多少千米？
<gadget id="calculator">36 + 27</gadget>
<output>63</output>

<gadget id="calculator">63 * 20</gadget>
<output>1_260</output>

<result>1_260</result>