Q. 65.0( 1 Vote )

# Mark the correct alternative in the following:

A fair die is thrown twenty times. The probability that on the tenth throw the fourth six appears is

A.

B.

C.

D. none of these

Ans. C

Answer :

Given:

Total outcomes= 6^{10}

Fourth 6 is at 10^{th} place.

So other three 6 have to be placed at any of the remaining 9 places=^{9}C_{3}5^{6}

For remaining 5 places we have 1,2,3,4&5

So total number of favorable cases

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A box has 100 pens of which 10 are defective. What is the probability that out of a sample of 5 pens drawn one by one with replacement at most one is defective?

Mathematics - ExemplarState True or False for the statements in the Exercise.

If A, B and C are three independent events such that P(A) = P(B) = P(C) = p, then

P (At least two of A, B, C occur) = 3p^{2} – 2p^{3}

A random variable X has the following probability distribution:

Determine:

(i) K (ii) P (X < 3)

(iii) P (X > 6) (iv) P (0 < X < 3)

**OR**

Find the probability of throwing at most 2 sixes in 6 throws of a single die

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