In a typical blood sample, the surface areas of the red blood cells have a normal distribution with a mean of 135 µm2 and a standard deviation of 20 µm2 . What fraction of the red blood cells has a surface area larger than 170 µm2

P(x > 170) = 0.04

Step-by-step explanation:

Since the the surface areas of the red blood cells in a typical blood sample have a normal distribution, we would apply the formula for normal distribution which is expressed as

z = (x - µ)/σ

Where

x = surface areas of red blood cells.

µ = mean surface area

σ = standard deviation

From the information given,

µ = 135 µm2

σ = 20 µm2

We want to find the fraction of the red blood cells that has a surface area larger than 170 µm2. It is expressed as

P(x > 170) = 1 - P(x ≤ 170)

For x = 170,

z = (170 - 135)/20 = 1.75

Looking at the normal distribution table, the probability corresponding to the z score is 0.96

P(x > 170) = 1 - 0.96

P(x > 170) = 0.04

7,24

step-by-step explanation:

the answer is 8/21

hope this