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Using the following information to answer the next two exercises: 64 faculty members were asked the number of cars they owned (including spouse and children’s cars). The results are given in the following graph:

This shows a relative frequency bar graph. The horizontal axis shows the number of cars using whole numbers from 0 to 6. The vertical axis shows relative frequency in units of 0.1 from 0.15 to 0.45. The graph shows the following proportions: 0.075 of responses are 1, 0.15 are 2, 0.45 are 3, 0.25 are 4, and 0.075 of responses are 6.

36. Find the approximate number of responses that were three.

37. Find the first, second and third quartiles. Use them to construct a box plot of the data.

Use the following information to answer the next three exercises: [link] shows data gathered from 15 girls on the Snow Leopard soccer team when they were asked how they liked to wear their hair. Supposed one girl from the team is randomly selected.

Hair Style/Hair Color Blond Brown Black
Ponytail 3 2 5
Plain 2 2 1

38. Find the probability that the girl has black hair GIVEN that she wears a ponytail.

39. Find the probability that the girl wears her hair plain OR has brown hair.

40. Find the probability that the girl has blond hair AND that she wears her hair plain.

Chapter 6

Use the following information to answer the next two exercises: X ~ U (3, 13)

41. Explain which of the following are false and which are true.

  1. f ( x ) = 1 10 , 3 ≤ x ≤ 13
  2. There is no mode
  3. The median is less than the mean.
  4. P ( x >10) = P ( x ≤ 6)

42. Calculate:

  1. the mean.
  2. the median.
  3. the 65 th percentile.

This is a boxplot over a number line  from 0 to 7. The left whisker ranges from minimum, 0, to lower quartile, 2. The box runs from lower quartile, 2, to upper quartile, 5. A dashed line marks the median at 4. The right whisker runs from 5 to maximum value 7.

43. Which of the following is true for the box plot in [link] ?

  1. Twenty-five percent of the data are at most five.
  2. There is about the same amount of data from 4–5 as there is from 5–7.
  3. There are no data values of three.
  4. Fifty percent of the data are four.

44. If P ( G | H ) = P ( G ), then which of the following is correct?

  1. G and H are mutually exclusive events.
  2. P ( G ) = P ( H )
  3. Knowing that H has occurred will affect the chance that G will happen.
  4. G and H are independent events.

45. If P ( J ) = 0.3, P ( K ) = 0.63, and J and K are independent events, then explain which are correct and which are incorrect.

  1. P ( J AND K ) = 0
  2. P ( J OR K ) = 0.9
  3. P ( J OR K ) = 0.72
  4. P ( J ) ≠ P ( J | K )

46. On average, five students from each high school class get full scholarships to four-year colleges. Assume that most high school classes have about 500 students. X = the number of students from a high school class that get full scholarships to four-year schools. Which of the following is the distribution of X ?

  1. P (5)
  2. B (500, 5)
  3. Exp ( 1 5 )
  4. N ( 5 , ( 0.01 ) ( 0.99 ) 500 )

Chapter 7

Use the following information to answer the next three exercises: Richard’s Furniture Company delivers furniture from 10 A.M. to 2 P.M. continuously and uniformly. We are interested in how long (in hours) past the 10 A.M. start time that individuals wait for their delivery.

47. X ~ _________

  1. U (0, 4)
  2. U (10, 20)
  3. Exp (2)
  4. N (2, 1)

48. The average wait time is:

  1. 1 hour.
  2. 2 hours.
  3. 2.5 hours.
  4. 4 hours.

49. Suppose that it is now past noon on a delivery day. The probability that a person must wait at least 1.5 more hours is:

  1. 1 4
  2. 1 2
  3. 3 4
  4. 3 8

50. Given: X ~ Exp ( 1 3 )

  1. Find P ( x >1).
  2. Calculate the minimum value for the upper quartile.
  3. Find P ( x = 1 3 )


  • 40% of full-time students took 4 years to graduate
  • 30% of full-time students took 5 years to graduate
  • 20% of full-time students took 6 years to graduate
  • 10% of full-time students took 7 years to graduate

The expected time for full-time students to graduate is:
  1. 4 years
  2. 4.5 years
  3. 5 years
  4. 5.5 years

Questions & Answers

discuss the roles of vital and health statistic in the planning of health service of the community
given that the probability of
can man city win Liverpool ?
Emmanuel Reply
There are two coins on a table. When both are flipped, one coin land on heads eith probability 0.5 while the other lands on head with probability 0.6. A coin is randomly selected from the table and flipped. (a) what is probability it lands on heads? (b) given that it lands on tail, what is the Condi
Nusrat Reply
what is gradient descent?
Saurav Reply
It should be a Machine learning terms。
it is a term used in linear regression
what are the differences between standard deviation and variancs?
what is statistics
Emmanuel Reply
statistics is the collection and interpretation of data
the science of summarization and description of numerical facts
Is the estimation of probability
mr. zaini..can u tell me more clearly how to calculated pair t test
do you have MG Akarwal Statistics' book Zaini?
Haai how r u?
maybe .... mathematics is the science of simplification and statistics is the interpretation of such values and its implications.
can we discuss about pair test
what is outlier?
Usama Reply
outlier is an observation point that is distant from other observations.
what is its effect on mode?
Outlier  have little effect on the mode of a given set of data.
How can you identify a possible outlier(s) in a data set.
The best visualisation method to identify the outlier is box and wisker method or boxplot diagram. The points which are located outside the max edge of wisker(both side) are considered as outlier.
@Daniel Adunkwah - Usually you can identify an outlier visually. They lie outside the observed pattern of the other data points, thus they're called outliers.
what is completeness?
I am new to this. I am trying to learn.
I am also new Dom, welcome!
please my friend i want same general points about statistics. say same thing
outliers do not have effect on mode
also new
I don't get the example
Hadekunle Reply
ways of collecting data at least 10 and explain
Ridwan Reply
Example of discrete variable
Bada Reply
sales made monthly.
I am new here, can I get someone to guide up?
dies outcome is 1, 2, 3, 4, 5, 6 nothing come outside of it. it is an example of discrete variable
continue variable is any value value between 0 to 1 it could be 4digit values eg 0.1, 0.21, 0.13, 0.623, 0.32
How to answer quantitative data
Alhassan Reply
what's up here ... am new here
sorry question a bit unclear...do you mean how do you analyze quantitative data? If yes, it depends on the specific question(s) you set in the beginning as well as on the data you collected. So the method of data analysis will be dependent on the data collecter and questions asked.
how to solve for degree of freedom
Quantitative data is the data in numeric form. For eg: Income of persons asked is 10,000. This data is quantitative data on the other hand data collected for either make or female is qualitative data.
Degree of freedom is the unconditionality. For example if you have total number of observations n, and you have to calculate variance, obviously you will need mean for that. Here mean is a condition, without which you cannot calculate variance. Therefore degree of freedom for variance will be n-1.
data that is best presented in categories like haircolor, food taste (good, bad, fair, terrible) constitutes qualitative data
vegetation types (grasslands, forests etc) qualitative data
I don't understand how you solved it can you teach me
Caleb Reply
solve what?
What is the end points of a confidence interval called?
lower and upper endpoints
Class members write down the average time (in hours, to the nearest half-hour) they sleep per night.
William Reply
how we make a classes of this(170.3,173.9,171.3,182.3,177.3,178.3,174.175.3)
why is always lower class bundry used
Assume you are in a class where quizzes are 20% of your grade, homework is 20%, exam _1 is 15%,exam _2 is 15%, and the final exam is 20%.Suppose you are in the fifth week and you just found out that you scored a 58/63 on the fist exam. You also know that you received 6/9,8/10,9/9 on the first
Diamatu Reply
quizzes as well as a 9/11,10/10,and 4.5/7 on the first three homework assignment. what is your current grade in the course?
the answer is 2.6
if putting y=3x examine that correlation coefficient between x and y=3x is 1.
Aadrsh Reply

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Source:  OpenStax, Introductory statistics. OpenStax CNX. May 06, 2016 Download for free at http://legacy.cnx.org/content/col11562/1.18
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