Blackjack table

Hard 4 versus a dealer 8 is a hit in basic strategy; splitting twos is only correct against 2–7, and standing or doubling a total of 4 is far worse.

Hard 13 versus a dealer 8 is a hit under basic strategy; standing loses too often to an 8.

Hard 15 against a dealer 8 is a hit under basic strategy; standing loses too often when the dealer finishes 17 or better.

Hard 11 versus a dealer 10 is a standard double: one more card has strong expected value and the extra bet is justified.

Hard 18 against a dealer 10 is a stand in basic strategy; hitting or doubling risks busting a strong total.

Hard 11 versus a dealer 9 is a clear double: one more card is likely to make a strong total, and the extra bet maximizes expected value.

A hard 20 is already a very strong total against a dealer 9, so standing is the clear basic-strategy play. Hitting or doubling risks busting a winning hand, and splitting tens gives up a near-certain advantage.

Hard 10 against a dealer 2 is a standard double: the upcard is weak and one more card is the highest-EV play.

A pair of jacks totals 20 against a dealer 8, which is a strong made hand. Standing is correct; splitting tens or taking another card would only worsen the expected value.

Soft 17 versus a dealer 3 is a standard double when doubling is allowed, since the ace gives a strong chance to improve without busting.

Pair of fours totals 8 against a dealer 4; basic strategy is to hit rather than split or double.

Soft 19 against a dealer 4 is a strong total; standing is the correct basic-strategy play and hitting risks busting a winning hand.

Hard 7 against a dealer 3 is too weak to stand or double, so the basic-strategy play is to hit and try to improve the total.

Hard 17 against a dealer 3 is a clear stand; hitting risks busting a made hand.

Hard 10 versus a dealer 8 is a standard double: the extra bet is justified by the strong chance of making a strong total.

Hard 11 against a dealer 4 is a clear double: the extra bet is favored and a single card is the right play.

Hard 13 versus a dealer 2 is a basic-strategy stand; the dealer is more likely to bust than to beat a made 13.

Hard 9 versus a dealer 6 is a standard double: the dealer is weak and doubling maximizes expected value.

Hard 8 against a dealer 6 is too weak to stand or double, so the correct basic-strategy play is to hit and try to improve the total.

Hard 18 against a dealer 6 is a clear stand: the total is strong and the dealer is likely to bust, while hitting risks busting a winning hand.

Hard 9 against a dealer 3 is a basic-strategy double: the dealer is weak enough that taking one more card for double the stake is the highest-EV play.