Congcong has 20 pencils and gave 4 to his younger brother. What percentage of the total number of branches are left?
聪聪有20支铅笔，送给弟弟4支．还剩下总支数的几分之几？
<gadget id="calculator">20 - 4</gadget>
<output>16</output>

<gadget id="calculator">16 / 20</gadget>
<output>4/5 = around 0.8</output>

<result>4/5 = around 0.8</result>