52 Cards
Suit \ Rank | Aces | Twos | Threes | Fours | Fives | Sixes | Sevens | Eights | Nines | Tens | Jacks | Queens | Kings |
Heart | A | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | J | Q | K |
Diamond | A | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | J | Q | K |
Club | A | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | J | Q | K |
Spade | A | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | J | Q | K |
Number of red cards = \(13 \times 2 \\ = 26\)
Number of jacks = 4
52P2 = 2652 ways to get two cards.
Number of ways to get 2 red cards:
26P2 = 650 ways to get two red cards
Number of ways to get 2 jacks:
4P2 = 12 ways
As the Jack of Hearts and Jack of Diamonds are considered two red cards, subtract one way.
We get 650 + 12 - 1 = 661 ways.
P(2 red card or 2 jacks) = \(661 \over 2652\)
= 0.24925 (correct to 5 significant figures)
= 24.925%