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1. Use the standard normal (z score) table to find: P(-1.00 z ) 2. The assets (i

ID: 3207718 • Letter: 1

Question

1. Use the standard normal (z score) table to find:

P(-1.00 z)

2. The assets (in billions of dollars) of the four wealthiest people in a particular country are

28, 26, 19, 18.

3. Assume that samples of size n =2 are randomly selected with replacement from this population of four values.

a. After identifying the 16 different possible samples and finding the mean of each sample, construct a table representing the sampling distribution of the sample mean. In the table, values of the sample mean that are the same have been combined.

x overbarx

Probability

x overbarx

Probability

28

22.5

27

22

26

19

23.5

18.5

23

18

(Type integers or fractions.)

Assume that women's heights are normally distributed with a mean given by =63.4 in,

and a standard deviation given by =2.5 in.

(a) If 1 woman is randomly selected, find the probability that her height is less than 64 in.

(b) If 35 women are randomly selected, find the probability that they have a mean height less than 64 in.

(a) The probability is approximately is    .

x overbarx

Probability

x overbarx

Probability

28

22.5

27

22

26

19

23.5

18.5

23

18

Explanation / Answer

1) P(-1<z) =1-P(Z<-1)=1-0.1587=0.8413

2)below is the table of sample mean drawn for n=2

from above

3) mean =63.4 and std deviation=2.5

a) P(X<64)=P(Z<(64-63.4)/2.5)=P(Z<0.24)=0.5948

b)for mean std error =std deviation/(n)1/2 =0.4226

P(X<64)=P(Z<64-63.4)/0.4226)=P(Z<1.42)=0.9222

1 2 mean 28 28 28 26 28 27 19 28 23.5 18 28 23 28 26 27 26 26 26 19 26 22.5 18 26 22 28 19 23.5 26 19 22.5 19 19 19 18 19 18.5 28 18 23 26 18 22 19 18 18.5 18 18 18