The number A is 75, the number B is 30% of the number A, what is the number B?
甲数是75，乙数是甲数的30%，乙数是多少．
<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">75 * (3/10)</gadget>
<output>45/2 = around 22.5</output>

<result>45/2 = around 22.5</result>