A colored ribbon is (5/4) meters long, and (2/5) of it is used for the first time, and (2/5) meters are used for the second time, how many meters is the remaining colored ribbon shorter than the original one?
一根彩带长(5/4)米，第一次用去它的(2/5)，第二次用去(2/5)米，剩下的彩带比原来短了多少米？
<gadget id="calculator">5 / 4</gadget>
<output>5/4 = around 1.25</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(5/4) * (2/5)</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(1/2) + (2/5)</gadget>
<output>9/10 = around 0.9</output>

<result>9/10 = around 0.9</result>