Respuesta :
Answer:
A. 97.72%
B. 0.13%
C. 15.87%
Step-by-step explanation:
Values in the graph:
μ = 20,200 σ = 40
μ + σ = 20,240
μ - σ = 20,160
μ + 2σ = 20,280
μ - 2σ = 20,120
μ + 3σ = 20,320
μ - 3σ = 20,080
Now, let's find the z-score for each question:
A. On what percent of the days last year did the factory produce 20,280 or fewer?
z-score = + 2.0 ⇒ p = 0.9772 = 97.72%
B. On what percent of the days last year did the factory produce 20,320 or more?
z-score = + 3.0 ⇒ p = 0.9987; 1 - 0.9987 = 0.0013 = 0.13%
C. On what percent of the days last year did the factory produce 20,160 or fewer?
z-score = - 1.0 ⇒ p = 0.1587 = 15.87%