23:["$","div",null,{"data-slot":"card","className":"bg-card text-card-foreground flex flex-col gap-6 rounded-xl border py-6 shadow-sm w-full","children":[["$","div",null,{"data-slot":"card-header","className":"@container/card-header grid auto-rows-min grid-rows-[auto_auto] items-start gap-2 px-6 has-data-[slot=card-action]:grid-cols-[1fr_auto] [.border-b]:pb-6 space-y-4","children":[["$","div",null,{"className":"flex justify-between items-start gap-4","children":[["$","div",null,{"className":"space-y-2","children":[["$","div",null,{"data-slot":"card-title","className":"text-2xl font-bold","children":"Expected Cards Until Second Ace"}],["$","p",null,{"className":"text-sm text-muted-foreground","children":["Source: ","1975 USAMO Problem 5"]}]]}],["$","div",null,{"className":"text-sm text-muted-foreground whitespace-nowrap","children":"March 15, 2010"}]]}],["$","div",null,{"className":"flex flex-wrap gap-2","children":[["$","span","106",{"data-slot":"badge","className":"inline-flex items-center justify-center rounded-full border px-2 py-0.5 text-xs font-medium w-fit whitespace-nowrap shrink-0 [&>svg]:size-3 gap-1 [&>svg]:pointer-events-none focus-visible:border-ring focus-visible:ring-ring/50 focus-visible:ring-[3px] aria-invalid:ring-destructive/20 dark:aria-invalid:ring-destructive/40 aria-invalid:border-destructive transition-[color,box-shadow] overflow-hidden border-transparent bg-secondary text-secondary-foreground [a&]:hover:bg-secondary/90","children":"probability"}],["$","span","114",{"data-slot":"badge","className":"inline-flex items-center justify-center rounded-full border px-2 py-0.5 text-xs font-medium w-fit whitespace-nowrap shrink-0 [&>svg]:size-3 gap-1 [&>svg]:pointer-events-none focus-visible:border-ring focus-visible:ring-ring/50 focus-visible:ring-[3px] aria-invalid:ring-destructive/20 dark:aria-invalid:ring-destructive/40 aria-invalid:border-destructive transition-[color,box-shadow] overflow-hidden border-transparent bg-secondary text-secondary-foreground [a&]:hover:bg-secondary/90","children":"symmetry"}],["$","span","238",{"data-slot":"badge","className":"inline-flex items-center justify-center rounded-full border px-2 py-0.5 text-xs font-medium w-fit whitespace-nowrap shrink-0 [&>svg]:size-3 gap-1 [&>svg]:pointer-events-none focus-visible:border-ring focus-visible:ring-ring/50 focus-visible:ring-[3px] aria-invalid:ring-destructive/20 dark:aria-invalid:ring-destructive/40 aria-invalid:border-destructive transition-[color,box-shadow] overflow-hidden border-transparent bg-secondary text-secondary-foreground [a&]:hover:bg-secondary/90","children":"expected value"}]]}]]}],["$","div",null,{"data-slot":"card-content","className":"px-6 space-y-8","children":[["$","section",null,{"className":"space-y-3","children":[["$","h2",null,{"className":"text-lg font-semibold","children":"Problem Statement"}],["$","div",null,{"className":"prose dark:prose-invert max-w-none bg-muted/30 p-4 rounded-lg","children":["$","div",null,{"className":"latex","children":["$","span",null,{"className":"__Latex__","dangerouslySetInnerHTML":{"__html":"A deck of

n

playing cards, which contains three aces, is shuffled at random (it is assumed that all possible card distributions are equally likely). The cards are then turned up one by one from the top until the second ace appears. Prove that the expected (average) number of cards to be turned up is (n\\plus{}1)/2."}}]}]}]]}],"$L25"]}]]}]