The blood cholesterol levels of men aged 55 to 64 are approximately normally distributed with mean 222 mg/dl and standard deviation 37 mg/dl.
We can estimate that 10% percent of the men aged 55 to 64 have cholesterol level mg/dl or higher. (round to an integer)

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:

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:

Thus, 10% of the men aged 55 to 64 have cholesterol level 270 mg/dl or higher.

x is the total time in minutes for the free response

you are given number of questions as 15 - m and time per item as 8 minutes

to find x multiply the two givens together:

x = 8 * (15-m) = 8(15-m)

step-by-step explanation: