Q. 154.0( 4 Votes )

A bag conta

Answer :


Bag contains 7 white, 5 black and 4 red balls

It is told that four balls are drawn without replacement.

We need to find the probability that at least three balls drawn are Black.

The possible cases of drawing balls are as shown below:

i. Black, Black, Black, Others

ii. Black, Black, Others, Black

iii. Black, Others, Black, Black

iv. Others, Black, Black, Black

v. Black, Black, Black, Black

P(Dat3blacks) = P(BBBO) + P(BBOB) + P(BOBB) + P(OBBB) + P(BBBB)

Since drawing balls are independent events so, the probabilities multiply each other.

The required probability is .

Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
view all courses

A bag contains 6 RD Sharma - Volume 2

A man is known toMathematics - Board Papers

A bag contaRD Sharma - Volume 2

Three persons A, Mathematics - Board Papers

Bag I contains 3 Mathematics - Board Papers

A speaks trRD Sharma - Volume 2

Two cards aRD Sharma - Volume 2

A bag contaRD Sharma - Volume 2

Kamal and MRD Sharma - Volume 2

Two balls aRD Sharma - Volume 2