Question

Refer to the accompanying technology display. The probabilities were obtained by entering the values of

n equals 5n=5

and

p equals 0.747p=0.747.

In a clinical test of a​ drug,

74.7​%

of the subjects treated with 10 mg of the drug experienced headaches. In each​ case, assume that

5

subjects are randomly selected and treated with 10 mg of the drug. Find the probability that at least four of the subjects experience headaches. Is it unusual to have fewer than four subjects experience​ headaches?

0	0.00100.0010
1	0.01530.0153
2	0.09040.0904
3	0.26680.2668
4	0.39390.3939
5	0.2326

The probability that at least four of the subjects experience headaches is

​(Round to four decimal places as​ needed.)

Is it unusual to have fewer than four subjects experience​ headaches?

A.

NoNo​,

because the probability that fewer than four subjects will experience headaches

isis

unlikely.

B.

NoNo​,

because the probability that fewer than four subjects will experience headaches

is notis not

unlikely.

C.

YesYes​,

because the probability that fewer than four subjects will experience headaches

is notis not

unlikely.

D.

YesYes​,

because the probability that fewer than four subjects will experience headaches

isis

unlikely.

Answer 1

Answer)

We need to find probability of atleast 4

That is p(4) + p(5)

By the probability distribution table

P(4) = 0.3939

P(5) = 0.2326

Required probability is 0.3939 + 0.2326

= 0.6265

Second part)

Fewer than 4 = p(0) + p(1) + p(2) + p(3)

= 0.001 + 0.0153 + 0.0904 + 0.2668

= 0.3735

We call the event unusual when the given probability is less than 0.05

As here the probability is 0.3735 which is greater than 0.05

So it is not unusual.

So, no because probability is not unlikely.