Data:
• Mean (μ) = 50
,
• Standard deviation (σ) = 3
,
• P( ,x >=47 ,)
Procedure:
1. Since μ = 50 and σ = 3:
[tex]P(x\le47)=P(X-\mu<47-50)=P(\frac{x-\mu}{\sigma}<\frac{47-50}{3})[/tex][tex]Z=\frac{x-\mu}{\sigma}[/tex][tex]\frac{47-50}{3}=-1[/tex]
2. Replacing the values:
[tex]P(x\le47)=P(Z\le-1)[/tex]
With this, we do not have to figure out what x is.
3. Using the standard normal table:
[tex]P(Z\le-1)=0.1587\approx0.16[/tex]
Answer: A. 0.16
