In a group there are 3 women and 3 men. 4 people are selected at random from this group -Maths 9th

1 Answer

Answer :

A : Selected 3 women and 1 man B : Selected 1 women and 3 men S : Selected 4 people from 6 people (3 + 3) Then n(A) = 3C3 × 3C1, n(B) = 3C1 × 3C3, n(S) = 6C4∴ Required probability = P(A) + P(B) = \(rac{n(A)}{n(S)}\) + \(rac{n(B)}{n(S)}\) = \(rac{^3C_3 imes^3C_1}{^6C_4}\) + \(rac{^3C_1 imes^3C_3}{^6C_4}\)= \(rac{2 imes1 imes3}{15}\) = \(rac{2}{5}.\)

Related questions

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Description : Two balls are drawn at random from a bag containing 3 white, 3 red, 4 green and 4 black balls, one by one without replacement. -Maths 9th

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Description : A bag contains 30 tickets numbered from 1 to 30. Five tickets are drawn at random and arranged in ascending order -Maths 9th

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Description : A bag contains 7 red and 5 green balls. The probability of drawing all four balls asred balls, when four balls are drawn at random is -Maths 9th

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