Xiao Ming is doing a coin toss game. Out of the first 9 times, 5 times it turned up heads and 4 times it turned up tails. What is the probability of turning up tails on the 10th toss?
小明做抛硬币游戏，前9次中有5次正面朝上，有4次反面朝上，第10次抛，反面朝上的可能性为多少
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

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