Determine the number of 5-card combinations out of a deck of 52 cards if there is exactly one ace in each combination.
There are 4 aces and 48 other cards in a deck of 52 cards. We have to select 1 ace out of 4 aces and 4 other cards out of 48 other cards.
∴ Number of ways of selection = 4C1×48C4
= 4×3!3!×48×47×46×45×44!4×3×2×44!
= 778320.