After the school was cleaned up, an inspection and evaluation was organized. 16 classes were qualified and 4 classes were unqualified. Seek the sanitation pass rate.
学校大扫除后，组织检查评比，有16个班合格，4个班不合格，求卫生合格率．
<gadget id="calculator">16 + 4</gadget>
<output>20</output>

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

<gadget id="calculator">100 / 100</gadget>
<output>1</output>

<gadget id="calculator">(4/5) * 1</gadget>
<output>4/5 = around 0.8</output>

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