โ† All AMC12 Flashcard Decks

Combinatorics & Probability Flashcards

6 cards from real AMC12 practice questions. Tap to flip, then mark Knew It or Still Learning โ€” missed cards come back until you master them.

Read the first 6 Combinatorics & Probability flashcards as text
  1. In how many ways can 5 people be arranged in a line?

    Answer: 120

    The number of permutations of 5 distinct people is 5!=120.

  2. A bag has 3 red and 5 blue balls. One ball is drawn at random. What is P(red)?

    Answer: 3/8

    3 red balls out of 8 total gives P(red)=3/8.

  3. How many ways can 3 people be chosen from a group of 8?

    Answer: 56

    C(8,3)=8!/(3!5!)=56.

  4. Two dice are rolled. What is the probability both show the same number?

    Answer: 1/6

    There are 6 matching outcomes out of 36 total: P=6/36=1/6.

  5. How many 3-letter strings (repetition allowed) can be formed from {A,B,C,D}?

    Answer: 64

    With 4 choices per position and 3 positions, the total is 4^3=64.

  6. From a 52-card deck, what is the probability of drawing an ace or a king?

    Answer: 2/13

    8 favorable cards (4 aces + 4 kings) out of 52 gives 8/52=2/13.