CA Foundation P3 · Chapter 16 · Question 2 of 9
The mean and variance of a binomial distribution are 6 and 4 respectively. The number of trials n is:
Test yourself: pick an answer
Reveal answer & explanation
Correct answer: C) 18
Explanation
np = 6 and npq = 4, so q = 4/6 = 2/3 and p = 1/3. Then n = 6/(1/3) = 18. Using p = 2/3 by mistake gives n = 9.
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