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10 girls...and 8 boys... teacher picks 3....probability of
teacher picking all 3 girls?

User Dolinda
by
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1 Answer

4 votes

Answer:

There is a 14.71% probability of teacher picking all 3 girls.

Explanation:

Initially, there are 18 students, of which 10 are girls. So there is a 10/18 = 5/9 probability that the first student chosen is a girl.

Now, since the first student chosen was a girl, there are 17 students, of which 9 are girls. So there is a 9/17 of the second student chosen being a girl.

Both students picked were girls. Now there are 16 students, of which 8 are girls. So there is a 8/16 = 1/2 probability of the third student chosen in this situation being a girl.

Probability of teacher picking all 3 girls?

We multiply these probabilities:


P = (5)/(9)*(9)/(17)*(1)/(2) = 0.1471

There is a 14.71% probability of teacher picking all 3 girls.

User Shidhin Cr
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