Group best

Try it in R:

sizeA <- 10
sizeB <- 2

M <- matrix(c(rep("A", sizeA), rep("B", sizeB), rep(NA, sizeA+sizeB)),
            nrow = sizeA+sizeB, ncol = 2)
M <- as.data.frame(M)
names(M) <- c("group", "score")


n <- 100000
maxA <- rep(NA, n)
maxB <- rep(NA, n)


for (i in 1:n){
  M$score <- sample(1:100, nrow(M), replace = T)
  maxA[i] <- max(M$score[M$group=="A"])
  maxB[i] <- max(M$score[M$group=="B"])
}
  
round(mean(maxA), 1);round(mean(maxB), 1)