There are two wires A and B. A is 20m longer than B. When both wires are used up by 25m, the remaining length of B is 80% of A. How long is A?
有甲、乙两根电线，甲根比乙根长20m，当两根电线都用去25m后，剩下的乙根长是甲根的80%，原来甲根电线有多长？
<gadget id="calculator">80 / 100</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">25 * (4/5)</gadget>
<output>20</output>

<gadget id="calculator">25 - 20</gadget>
<output>5</output>

<gadget id="calculator">20 + 5</gadget>
<output>25</output>

<gadget id="calculator">1 - (4/5)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">25 / (1/5)</gadget>
<output>125</output>

<result>125</result>