According to statistics, blue whales can swim 108 meters in 3 hours, and dolphins can swim 245 meters in 5 hours. How much less can blue whales swim per hour than dolphins?
据统计蓝鲸3小时能游108米，海豚5小时能游245米，蓝鲸每小时比海豚少游多少米？
<gadget id="calculator">245 / 5</gadget>
<output>49</output>

<gadget id="calculator">108 / 3</gadget>
<output>36</output>

<gadget id="calculator">49 - 36</gadget>
<output>13</output>

<result>13</result>