Uncle Wang sorts out a piece of land at a rate of 6.4m**2 per minute, which can be finished in half an hour. If 1.6m**2 is sorted per minute, how many hours can it be finished? (Solve with ratio)
王大爷整理一块地，每分钟整理6.4m**2，半小时可以整理完毕．如果每分钟多整理1.6m**2，多少小时可以整理完毕？(用比例解)
<result>14</result>