The number of A is 80, the number of B is less than the number of A (1/4), what is the number of B?
甲数是80，乙数比甲数少(1/4)，乙数是多少．
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (1/4)</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">80 * (3/4)</gadget>
<output>60</output>

<result>60</result>