The ratio of number A to number B is 2:5, how much less number A is than number B.
甲数和乙数的比是2：5，甲数比乙数少多少．
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<result>3/5 = around 0.6</result>