CA Foundation · Quantitative Aptitude · Theoretical Distributions
For a binomial distribution with n = 10 and p = 0.3, what is the mean of the distribution?
The mean of a binomial distribution is np. Here n is 10 and p is 0.3, so the mean is 3. The figure 2.1 is the variance npq, and 7 is the expected number of failures, so neither is the mean.
- A3Correct
- B2.1
- C7
- D3.3
Explanation
Mean of a binomial distribution = np = 10 × 0.3 = 3. The value 2.1 is the variance npq = 10 × 0.3 × 0.7, which is a different measure. The value 7 is nq, the expected number of failures.
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