Engineering Board Exam Reviewer · Binomial Distribution · hard
A binomial distribution has mean 12 and variance 8. Find the number of trials n.
- 24
- 18
- 4
- 36
Answer
D. 36
Solution
np=12 and npq=8. Dividing: q=8/12= 23, so p= 13. Then n=12/1/3=36.
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