{"id":7010,"date":"2021-10-22T14:46:01","date_gmt":"2021-10-22T09:16:01","guid":{"rendered":"https:\/\/mathemerize.com\/?p=7010"},"modified":"2021-10-25T09:37:04","modified_gmt":"2021-10-25T04:07:04","slug":"the-mean-and-the-variance-of-a-binomial-distribution-are-4-and-2-respectively-then-the-probability-of-2-success-is","status":"publish","type":"post","link":"https:\/\/mathemerize.com\/the-mean-and-the-variance-of-a-binomial-distribution-are-4-and-2-respectively-then-the-probability-of-2-success-is\/","title":{"rendered":"The mean and the variance of a binomial distribution are 4 and 2, respectively. Then, the probability of 2 success is"},"content":{"rendered":"
Given that, mean = 4 \\(\\implies\\) np = 4<\/p>\n
And Variance = 2 \\(\\implies\\) npq = 2 \\(\\implies\\) 4q = 2<\/p>\n
\\(\\implies\\)\u00a0 q = \\(1\\over 2\\)<\/p>\n
\\(\\therefore\\)\u00a0 \u00a0p = 1 – q = 1 – \\(1\\over 2\\) = \\(1\\over 2\\)<\/p>\n
Also, n = 8<\/p>\n
Probability of 2 successes = P(X = 2) = \\(^8C_2\\)\\(p^2\\)\\(q^6\\)<\/p>\n
= \\(8!\\over {2!\\times 6!}\\) \\(\\times\\) \\(({1\\over 2})^2\\) \\(\\times\\) \\(({1\\over 2})^2\\)<\/p>\n
= \\(28\\over 256\\)<\/p>\n
The mean and variance of a random variable X having a binomial distribution are 4 and 2 respectively, then P(X = 1) is<\/a><\/p>\n The median of a set of 9 distinct observations is 20.5. If each of the largest 4 observation of the set is increased by 2, then the median of the new is<\/a><\/p>\n Suppose a population A has 100 observation 101, 102, \u2026.. , 200 and another population B has 100 observations 151, 152, \u2026. , 250. If \\(V_A\\) and \\(V_B\\) represent the variance of the two populations respectively, then \\(V_A\\over V_B\\) is<\/a><\/p>\n In a series of 2n observations, half of them equals a and remaining half equal -a. If the standard deviation of the observation is 2, then |a| equal to<\/a><\/p>\n