If a coin is tossed 5 times, heads come up 4 times and tails once, the chance of tails on the next toss is ((())/(())).
把一枚硬币，抛了5次，出现4次正面，一次反面，下次抛时出现反面的机会是((())/(()))．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<result>1/2 = around 0.5</result>