A pen costs 5 yuan, 40 cents and 8 cents, how much is it written as a decimal.
一支钢笔是5元4角8分钱，写成小数是多少元．
<gadget id="calculator">4 / 10</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">8 / 100</gadget>
<output>2/25 = around 0.08</output>

<gadget id="calculator">(2/5) + (2/25) + 5</gadget>
<output>137/25 = around 5.48</output>

<result>137/25 = around 5.48</result>