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You are at a European beach with 60 other visitors. 36 of them speak English. If you randomly meet two people on the beach, what is the probability that they both speak English?If you randomly meet three people on the beach, what is the probability that AT LEAST ONE of them speaks English?

1 Answer

6 votes

36 out of 60 people speak english

If you randomly meet the first one, the probability that this person speaks english is 36/60 = 0.6

When you meet the second person, the probability that this second person speaks english is 35/59 = 0.593220339

The probability that both of them speak english is the mulitplication of this two probabilities: (0.6) times 0.593220339

which is: 0.03559322034, of 3.6%

Fist answer:

The probability that they both speak English: 3.6%

If you randomly meet three people on the beach, what is the probability that AT LEAST ONE of them speaks English?​

The first person probability that speaks english: 36/60 = 0.6

The second person probability that speaks english: 35/59 = 0.593220339

The third person probability that speaks english: 34/58 = 0.5862068966

Probaility of at leat one of this three happening = 0.2086 ==> 20.9%

Second answer:

Probability that AT LEAST ONE of them speaks English is 20.9%

User JensB
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