In a weaving factory, each worker used to weave 77 meters per hour, but now weaves 648 meters in 8 hours. How much more is weaving per hour than before?
一个织布厂原来每个工人每小时织布77米，现在8小时织布648米，现在每小时比原来每小时多织布多少米？
<gadget id="calculator">648 / 8</gadget>
<output>81</output>

<gadget id="calculator">81 - 77</gadget>
<output>4</output>

<result>4</result>