Answer :
Answer:
It is provided that 10% of the men aged 55 to 64 have cholesterol level 270 mg/dl or higher.
Step-by-step explanation:
Let X = blood cholesterol levels of men aged 55 to 64 years.
The random variable X follows a Normal distribution with mean μ = 222 mg/dl and standard deviation σ = 37 mg/dl.
It is provided that 10% of the men aged 55 to 64 have cholesterol level x mg/dl or higher.
Compute the value of x as follows:
[tex]P(X\geq x)=0.10\\P(\frac{X-\mu}{\sigma}\geq \frac{x-222}{37})=0.10\\P(Z\geq z)=0.10\\1-P(Z<z)=0.10\\P(Z<z)=0.90[/tex]
Use the z-table to compute the value z for the probability 0.90.
The value of z is 1.29.
Compute the value of x as follows:
[tex]z=\frac{x-\mu}{\sigma}\\1.29=\frac{x-222}{37} \\x=222+(1.29\times37)\\=269.73\approx270[/tex]
Thus, 10% of the men aged 55 to 64 have cholesterol level 270 mg/dl or higher.
