Match List - I with List - II. List I — n = number of trials, p = probability…

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Match List - I with List - II.

List I — n = number of trials, p = probability of success

List II — Variance of Binomial Distribution

A. n = 7, p = 0.3

I. 1.44

B. n = 5, p = 0.4

II. 2.00

C. n = 8, p = 0.5

III. 1.20

D. n = 6, p = 0.6

IV. 1.47

Choose the correct answer from the options given below :

Answer: D. A-IV, B-III, C-II, D-IConceptFor a binomial random variable X with parameters n and p, the variance is Var(X) = npq, where q = 1 − p. The factor p(1 − p) is the variance of one…

  1. A.

    A-I, B-II, C-III, D-IV

  2. B.

    A-II, B-III, C-IV, D-I

  3. C.

    A-III, B-IV, C-I, D-II

  4. D.

    A-IV, B-III, C-II, D-I

Show answer & explanation

Correct answer: D

Concept

For a binomial random variable X with parameters n and p, the variance is Var(X) = npq, where q = 1 − p. The factor p(1 − p) is the variance of one Bernoulli trial, and multiplying it by n combines the contributions of n independent trials.

Application

  1. For A, q = 1 − 0.3 = 0.7, so the variance is 7 × 0.3 × 0.7 = 1.47. Therefore, A maps to IV.

  2. For B, q = 1 − 0.4 = 0.6, so the variance is 5 × 0.4 × 0.6 = 1.20. Therefore, B maps to III.

  3. For C, q = 1 − 0.5 = 0.5, so the variance is 8 × 0.5 × 0.5 = 2.00. Therefore, C maps to II.

  4. For D, q = 1 − 0.6 = 0.4, so the variance is 6 × 0.6 × 0.4 = 1.44. Therefore, D maps to I.

Cross-check

The four computations use each listed variance exactly once: A–IV, B–III, C–II, and D–I. Thus the accepted mapping is A-IV, B-III, C-II, D-I.

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