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DATA: Student What is your gender? How old are you? What is your height in inche

ID: 2933702 • Letter: D

Question

DATA:

Student

What is your gender?

How old are you?

What is your height in inches?

What is your cumulative Grade Point Average (GPA) at FTCC or your primary college?

How many hours do you sleep each night?

1

Male

20

68

3.67

6

2

Female

18

56

3.8

7

3

Female

43

67

3.89

7

4

Female

27

64

3.7

6

5

Female

22

67

3.4

7

6

Female

31

67

3.55

8

7

Female

22

64

2.5

6

8

Female

26

67

2.05

7

9

Male

38

71

0

8

10

Female

25

65

3.5

6

11

Female

28

65

4

4

12

Female

19

63

4

6

13

Female

17

65

0

7

14

Male

17

71

2

9

15

Male

33

68

3

7

16

Female

31

65

4

8

17

Female

19

55

2.5

7

18

Female

25

58

3

8

19

Male

30

69

3.82

7

20

Female

20

64

3.2

6

21

Female

31

69

3.78

6

22

Male

49

70

4

4

23

Female

23

52

2.5

6

24

Female

27

67

2.8

8

25

Male

18

69

0

6

26

Female

41

63

4

6

27

Female

25

60

3

6

28

Male

17

65

3.8

6

29

Female

17

66

4

6

30

Female

30

67

3.82

5

31

Male

17

72

3.44

6

32

Male

19

71

4

7

33

Male

29

56

3.75

4

34

Male

28

68

3.5

7

35

Male

29

69

1.9

8

36

Male

50

73

2.87

6

37

Female

16

67

4

8

38

Female

34

66

3.2

6

39

Female

38

65

4

6

40

Female

24

63

3.2

6

41

Female

34

66

3.2

6

42

Female

19

66

3.68

8

43

Female

24

63

3

7

44

Female

21

63

2.3

5

45

Female

51

66

3

5

46

Female

18

61

3.9

8

47

Male

36

71

2

6

48

Female

20

64

2

7

49

Male

20

69

3

8

50

Female

22

62

2.8

8

51

Female

17

67

0

8

52

Female

25

59

3

8

Question:

Height of Adults in US - Height of adults are known to be normally distributed with a mean of 69 inches and a standard deviation of 2.5 inches

Find the following: (Round each probability to four decimal places)

Find the probability that a randomly selected adult US adult has a height less than 64 inches tall.

Find the mean of the heights that I collected from statistics students at FTCC. Use data set. (Round to one decimal place.)

Find the probability that a random sample of 52 adults would have a mean height that is less the value from #2 above.

Find the following values:

Find the z score for #1 and #3 in part A above (Round each to the nearest hundredth.)

Find the height, x-value, for each percentile: Low 15%, Top 10%, and Middle 90%. (Round each to the nearest tenth.)

Student

What is your gender?

How old are you?

What is your height in inches?

What is your cumulative Grade Point Average (GPA) at FTCC or your primary college?

How many hours do you sleep each night?

1

Male

20

68

3.67

6

2

Female

18

56

3.8

7

3

Female

43

67

3.89

7

4

Female

27

64

3.7

6

5

Female

22

67

3.4

7

6

Female

31

67

3.55

8

7

Female

22

64

2.5

6

8

Female

26

67

2.05

7

9

Male

38

71

0

8

10

Female

25

65

3.5

6

11

Female

28

65

4

4

12

Female

19

63

4

6

13

Female

17

65

0

7

14

Male

17

71

2

9

15

Male

33

68

3

7

16

Female

31

65

4

8

17

Female

19

55

2.5

7

18

Female

25

58

3

8

19

Male

30

69

3.82

7

20

Female

20

64

3.2

6

21

Female

31

69

3.78

6

22

Male

49

70

4

4

23

Female

23

52

2.5

6

24

Female

27

67

2.8

8

25

Male

18

69

0

6

26

Female

41

63

4

6

27

Female

25

60

3

6

28

Male

17

65

3.8

6

29

Female

17

66

4

6

30

Female

30

67

3.82

5

31

Male

17

72

3.44

6

32

Male

19

71

4

7

33

Male

29

56

3.75

4

34

Male

28

68

3.5

7

35

Male

29

69

1.9

8

36

Male

50

73

2.87

6

37

Female

16

67

4

8

38

Female

34

66

3.2

6

39

Female

38

65

4

6

40

Female

24

63

3.2

6

41

Female

34

66

3.2

6

42

Female

19

66

3.68

8

43

Female

24

63

3

7

44

Female

21

63

2.3

5

45

Female

51

66

3

5

46

Female

18

61

3.9

8

47

Male

36

71

2

6

48

Female

20

64

2

7

49

Male

20

69

3

8

50

Female

22

62

2.8

8

51

Female

17

67

0

8

52

Female

25

59

3

8

Explanation / Answer

Height of Adults in US - Height of adults are known to be normally distributed with a mean of 69 inches and a standard deviation of 2.5 inches

Find the following: (Round each probability to four decimal places)

Find the probability that a randomly selected adult US adult has a height less than 64 inches tall.

Answer : Pr(X < 64 inch) = Pr( X < 64 inch ; 69 inch; 2.5 inch)

Z = (64 - 69)/2.5 = -2

Pr(X < 64 inch) = Pr( X < 64 inch ; 69 inch; 2.5 inch)  = Pr(Z < -2) = 0.0228

Find the mean of the heights that I collected from statistics students at FTCC. Use data set. (Round to one decimal place.)

Mean of the sample height = 65.3 inch

Find the probability that a random sample of 52 adults would have a mean height that is less the value from #2 above.

Answer : Standard error of the sample mean = / sqrt(n) = 2.5/ sqrt(52) = 0.3467

Pr(x < 65.3 ) = Pr(x < 65.3; 69; 0.3467)

Z = (65.3 - 69)/ 0.3467 = -10.67

Find the following values:

Find the z score for #1 and #3 in part A above (Round each to the nearest hundredth.)

Z#1 = -2

Z#2 = -10.67

Find the height, x-value, for each percentile: Low 15%, Top 10%, and Middle 90%. (Round each to the nearest tenth.)

Low 15%

so Pr(X <x ; 69; 2.5) = 0.15

so Z value for p = 0.15 is

Z = -1.0364

(x - 69)/2.5 = -1.0634

x = 69 - 2.5 * 1.0634 = 66.34 inch

Top 10%

Pr(X <x ; 69; 2.5) = 1 - 0.10 = 0.90

so Z value for p = 0.90 is

Z = 1.28

(x - 69)/2.5 = 1.28

x = 69 + 2.5 * 1.28 = 72.2 inch

Middle 90%

90% interval = 69 +- 1.96 * 2.5 = (64.1 inch, 73.9 inch)