>>137
百万回のシミュレーション結果

> mean(replicate(1e6,sim()))
[1] 0.54513

sim=\(){
cards=sample(12)
6 %in% c(sort(cards[1:3])[2],sort(cards[4:6])[2],sort(cards[7:9])[2],sort(cards[10:12])[2])
}
mean(replicate(1e6,sim()))