The fruit market needs to pack some fruits into boxes. If each box weighs 3 kilograms, it can hold 30 boxes. How many boxes can be saved if each box is 5 kg?
水果市场要将一些水果装箱，如果每箱3千克，可装30箱．如果每箱5千克，可少装多少箱？
<gadget id="calculator">30 / 5</gadget>
<output>6</output>

<gadget id="calculator">3 * 6</gadget>
<output>18</output>

<gadget id="calculator">30 - 18</gadget>
<output>12</output>

<result>12</result>