The number of cars passing a checkpoint per minute has μ = 12 and σ = 3. A sample of n = 36 minutes is recorded.
What is approximate P(x̄ > 13)?
- A
≈ 0.1587
- Bcheck_circle
≈ 0.0228
- C
≈ 0.3085
- D
≈ 0.5000
Explanation
σ_x̄ = 3/√36 = 0.5. z = 1/0.5 = 2. P(Z > 2) ≈ 0.0228.