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Questions › JNU › JNU SIS 2020 › Q50
0 marksStatistics › Random variables and standard distributions › The binomial distributionEasyabout 1 min

JNU SIS 2020 Question 50: Random variables and standard distributions

Consider a random variable X where P(X=k)=20!  0.25k (0.75)20−kk! (20−k)!P(X = k) = \dfrac{20!\;0.25^{k}\,(0.75)^{20-k}}{k!\,(20-k)!}P(X=k)=k!(20−k)!20!0.25k(0.75)20−k​ For k = 0, 1, 2, . . . , 20 What is the mean of X ?

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Consider a random variable X where P(X = k) = (20! 0.25^k (0.75)^(20-k))/(k! (20-k)!) For k = 0, 1, 2,..., 20 What is the mean of X? (A) 2.5 (B) 5 (C) 7.5 (D) 3

Random variables and standard distributions has come up 173 times in 7 exams since 2005.

What this question tests

This question is on The binomial distribution, part of Random variables and standard distributions in Statistics.

The number of successes in a fixed number of independent trials.

TestStop has 21 past-paper questions on this subtopic.

Practise Random variables and standard distributionsMore on The binomial distribution

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