Coloured balls are distributed in four boxes as shown in the following table:
Box |
Colour |
|||
Black |
White |
Red |
Blue |
|
I |
3 |
4 |
5 |
6 |
II |
2 |
2 |
2 |
2 |
III |
1 |
2 |
3 |
1 |
IV |
4 |
3 |
1 |
5 |
Suppose we have four boxes A, B, C and D containing coloured marbles as given below:
Box |
Marble Colour |
||
Red |
White |
Black |
|
A |
1 |
6 |
3 |
B |
6 |
2 |
2 |
C |
8 |
1 |
1 |
D |
0 |
6 |
4 |
One of the boxes has been selected at random and a single marble is drawn from it. If the marble is red. what is the probability that it was drawn from box A? box B? box C?
Number of red balls = 5
Number of black balls = 2
These two balls may be selected as RR, RB, BR, BB, where R represents red and B represents black ball.
Variable X has the value 0, 1, 2 i.e., there may be no black balls, may be one black ball, or both the balls are black.
Yes, X is a random variable.