Question

In a binomial distribution n = 5, P(X = 1) = 0.4096 and P(X = 2) = 0.2048, then the mean of the distribution is equal to ______.

Options

• 1

• 1.5

• 2

• 2.5

Answer 1

In a binomial distribution n = 5, P(X = 1) = 0.4096 and P(X = 2) = 0.2048, then the mean of the distribution is equal to 1.

Explanation:

0.4096 = ⁵C₁pq⁴

0.2048 = ⁵C₂p²q³ where p + q = 1

`\implies` p = `1/5`, q = `4/5`

Mean = np = 1