E-StoreHome » Ask & Discuss » Mathematics. » Algebra « Back to Discussion
Algebra
Comments (10)
Answer is 1/3
It is given that 2 balls are drawn at random and found to be white, it implies that there are at least 2 white balls.
Since total no. of balls are 4, no. of possibilities for the balance 2 balls are :
a. 0 white, 2 non-white,
b. 1 white, 1 non-white,
c. 2 white, 0 non-white.
Thus there are 3 possibilities of the combination of white and non-white balls exists in totality and
the no. of possibilities of 4 white balls are one out of the total possibilities of 3 .
Hence the probability of 4 white balls is 1/3
it is the case of white or any other color...we know that two of the balls are white..and the rest may be any color....
P(white ball known) = 1/2
p(other two balls being white) =1/3( as explained above)by another person :)
P(other two balls not being white)=2/3
by baye's theorem
we can conclude that the probability is (1/6)/(1/6 + 1/3)
this makes it 1/3...this is a correct explanation
Preparing for IIT-JEE ?
Arihant Revision Package for IIT JEE - Books, Practice Tests + Rank Predictor
@ INR 1,995/-
For Quick Info
Find Posts by Topics
Physics.
TopicsMathematics.
Chemistry.
Biology
Institutes
Parents
Board
Fun Zone
|
|
|
|
|
| 35,229,755 Engineering Questions Attempted |
6,69,530 Visitors Monthly |
79 Engg. Exam Covered |
1982 Students Currently Online |
Connect with Us  |
 |
