Combination Calculator
What is 10 choose 3?
10 choose 3 without repeats is 120.
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Exact answers to common counting and probability questions
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Permutation Calculator
What is 8P4?
8 permute 4 without repeats is 1,680.
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What is 6!?
6! is 720.
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What is 15C5?
The binomial coefficient C(15, 5) is 3,003.
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How many 10 digit PINs are possible?
10 choices for 10 ordered positions gives 10,000,000,000.
Open answer pageProbability Calculator
What is the probability of drawing a heart from a standard deck?
The probability is 1/4, which is 0.25 or 25%.
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What is the probability of at least 1 head in 4 coin flips?
The probability of at least 1 success is 93.75%.
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What is the probability of exactly 2 heads in 4 coin flips?
The probability of exactly 2 successes is 37.5%.
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What is the probability of at least 1 ace in a 5 card hand?
The probability of at least 1 success is 34.1158%.
Open answer pageBinomial Coefficient Calculator
What is 17C4?
The binomial coefficient C(17, 4) is 2,380.
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What is 25C3?
The binomial coefficient C(25, 3) is 2,300.
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How many 8 digit PINs are possible?
10 choices for 8 ordered positions gives 100,000,000.
Open answer pageFactorial Calculator
What is 11!?
11! is 39,916,800.
Open answer pageCircular Permutation Calculator
How many ways can 9 people sit around a round table?
9 distinct items around a circle can be arranged in 40,320 ways.
Open answer pageMultiset Permutation Calculator
How many distinct arrangements of the letters in the word SUCCESS are there?
For item-group counts 3, 2, 1, 1, the number of distinct arrangements is 420.
Open answer pageProbability Calculator
What is the probability of drawing an ace from a standard deck?
The probability is 1/13, which is 0.076923 or 7.6923%.
Open answer pageBinomial Probability Calculator
What is the probability of exactly 3 heads in 5 coin flips?
The probability of exactly 3 successes is 31.25%.
Open answer pageHypergeometric Probability Calculator
What is the probability of drawing exactly 2 aces in a 5 card hand?
The probability of exactly 2 successes is 3.993%.
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