58 bananas, 6 in each basket, how many bananas can be removed, and 9 baskets can be filled exactly.
58个香蕉，每篮装6个，拿掉多少个，就可以正好装9个篮子了．
<gadget id="calculator">6 * 9</gadget>
<output>54</output>

<gadget id="calculator">58 - 54</gadget>
<output>4</output>

<result>4</result>