(1/4) of the number A is equal to (2/5) of the number B. What fraction of the number A is the number B? What is the fraction of the sum of the two numbers?
甲数的(1/4)等于乙数的(2/5)，甲数是乙数的几分之几？乙数是两数和的几分之几？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(2/5) / (1/4) / 1</gadget>
<output>8/5 = around 1.6</output>

<gadget id="calculator">1 * (8/5)</gadget>
<output>8/5 = around 1.6</output>

<gadget id="calculator">1 + (8/5)</gadget>
<output>13/5 = around 2.6</output>

<gadget id="calculator">1 / (13/5)</gadget>
<output>5/13 = around 0.384615</output>

<result>5/13 = around 0.384615</result>