Let's tackle each of the probability questions one by one.

1. Probability of drawing a 4 of one suit

A deck of cards has 52 cards in total, and there is exactly one 4 in each of the four suits (clubs, spades, hearts, diamonds). Therefore, there are only 4 cards in the deck that are a 4, one for each suit.

• Total number of favorable outcomes: 1 (for a specific suit, say 4 of hearts)
• Total possible outcomes: 52

Thus, the probability is:

$P(\text{4 of one suit}) = \frac{1}{52}$

2. Probability of drawing a heart or spade

A deck has 13 hearts and 13 spades (total 26 cards that are either hearts or spades).

• Total number of favorable outcomes: 13 (hearts) + 13 (spades) = 26
• Total possible outcomes: 52

Thus, the probability is:

$P(\text{heart or spade}) = \frac{26}{52} = \frac{1}{2}$

3. Probability of drawing a number smaller than 4 (Ace as 1)

The numbers smaller than 4 are Ace (1), 2, and 3. Each suit has one of these cards, so there are 3 cards per suit across 4 suits.

• Total number of favorable outcomes: 3 cards (Ace, 2, 3) × 4 suits = 12
• Total possible outcomes: 52

Thus, the probability is:

$P(\text{number smaller than 4}) = \frac{12}{52} = \frac{3}{13}$

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Let me know if you need further details or clarifications. Here are 5 related questions you might find interesting:

1. What is the probability of drawing a face card (Jack, Queen, or King)?
2. What is the probability of drawing a red card?
3. What is the probability of drawing a card that is a diamond or a king?
4. What is the probability of drawing a card that is not a face card?
5. What is the probability of drawing a spade or a card less than 5?

Tip: Remember to always reduce fractions when presenting probabilities!