What is the sum of the counting unit of 0.28 and the fractional unit of (4/5).
0.28的计数单位与(4/5)的分数单位之和是多少．
<gadget id="calculator">1 / 100</gadget>
<output>1/100 = around 0.01</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(1/100) + (1/5)</gadget>
<output>21/100 = around 0.21</output>

<result>21/100 = around 0.21</result>