CA Foundation · Quantitative Aptitude · Theoretical Distributions
A pharmaceutical company observes that medication prescriptions follow a binomial distribution where the probability of a patient showing improvement is 0.6, and they conduct a trial with 10 patients. What is the expected number of patients showing improvement?
The expected number is 6 patients. For a binomial distribution, the mean is calculated as E(X) = n × p = 10 × 0.6 = 6, representing the average outcome across many trials.
- A4
- B6Correct
- C5
- D7
Explanation
For a binomial distribution B(n, p), the expected value is E(X) = n × p. Here, n = 10 and p = 0.6, so E(X) = 10 × 0.6 = 6. Option 4 would come from using p = 0.4 (the complement); option 5 would result from averaging the parameters incorrectly.
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