Easy -1.2 This is a straightforward recall question requiring only the binomial variance formula σ² = np(1-p). Students substitute p=1/3, σ=4, solve 16 = n(1/3)(2/3) to get n=72, then circle the answer. Single-step calculation with no problem-solving or conceptual challenge beyond formula recall.
The random variable \(X\) is such that \(X \sim B\left(n, \frac{1}{3}\right)\)
The standard deviation of \(X\) is 4
Find the value of \(n\).
Circle your answer.
[1 mark]
9 \quad 12 \quad 18 \quad 72
The random variable $X$ is such that $X \sim B\left(n, \frac{1}{3}\right)$
The standard deviation of $X$ is 4
Find the value of $n$.
Circle your answer.
[1 mark]
9 \quad 12 \quad 18 \quad 72
\hfill \mbox{\textit{AQA AS Paper 2 2020 Q13 [1]}}