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A die is thrown again and again until three sixes are obtained. Find the probability of obtaining the third six in the sixth throw of the die.
From the condition given in the question, it is clear that:
Probability of getting a six in a throw of die =
And, probability of not getting a six =
Let us assume,
Now, we have:
Probability that the 2 sixes come in the first five throws of the die
=
Also, Probability that the six come in the sixth throw
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?