30 apples, after dividing 1/3 of 30, how many apples are left.
30个苹果，分掉了30个的(1/3)后，还剩下多少个苹果．
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">30 * (1/3)</gadget>
<output>10</output>

<gadget id="calculator">30 - 10</gadget>
<output>20</output>

<result>20</result>