One moon cake is divided into 4 pieces on average, Xiao Liang ate 3 pieces, how much is left?
一个月饼，平均分成4块，小亮吃了3块，还剩下几分之几？
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">1 - (3/4)</gadget>
<output>1/4 = around 0.25</output>

<result>1/4 = around 0.25</result>