Question

Twenty percent of Americans ages 25 to 74 have high blood pressure. If 16 randomly selected Americans ages 25 to 74 are selected, find each probability.

A. One half will have high blood pressure.

Answer 1

Answer:

$0.0055$

Step-by-step explanation:

This is a binomial probabilty distribution problem.

The formula is:

$P(x=r)=nCr* p^{r}q^{n-r}$

Where

n is the total number of trials

r is the number of trials we want

p is the probabilty of success

q is 1 - p [probability of failure]

Here, we take 16 people, so n = 16

we want probability of hallf will have high blood pressure, that is 16*0.5 = 8

so r = 8

p is probabilty of that happening, which is 20% , p = 0.2

q = 1 - 0.2 = 0.8

Now putting into formula, we have:

$P(x=8)=16C8* (0.2)^{8}(0.8)^{16-8}\\=0.0055$

Hence

probability one half will have high blood pressure is 0.0055