Number A is 70% of Number B, how much less is Number A than Number B
甲数是乙数的70%，甲数比乙数少多少
<gadget id="calculator">70 / 100</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">1 - (7/10)</gadget>
<output>3/10 = around 0.3</output>

<result>3/10 = around 0.3</result>