Stats Ch 2 HW

Use the stem and leaf plot to list the actual data entries. What are the correction data entries? What is the maximum data entry? What is the minimum data entry?

A. 26, 32, 41, 42, 42, 45... B. Maximum data entry is 84 C. Minimum data entry is 26

The following frequency histogram represents the IQ scores of a random sample of seventh grade students. IQs are measured to the nearest whole number. The frequency of each class is labeled above each rectangle. Use the histogram to answer parts a through G. A. How many students were sampled? B. Determine the class width C. Identify the classes in their frequencies. Choose the correct answer below. D. Which class has the highest frequency? E. Which class has the lowest frequency? F. What percent of students has an IQ of at least 120? G. Did any student have an IQ of 162?

A. Add up all the frequencies listed at the top, to equal 200 students who were sampled B. The class with is 10, because it's the span of every class. C. The classes and their frequency are 60 to 69, one. 70-79, three. Continued. Notice how they don't overlap. D. The class of 100 to 109 has a frequency of 50. So it is highest E. The class of 60-69 only has 1 frequency. So it is lowest F. Add up all of the students that fall within the frequency of 120 to 160. That equals 42. Now divide 42 by 200 students which gives .21. Multiply that by 100 and you get 21% G. No, there are no bars, or frequencies greater than an IQ of 160

An experiment was conducted in which to fair dice were thrown 100 times. The sum of the pips showing on the days were then recorded. The frequency histogram to the right gives the results. Use the histogram to complete parts a through F A. What was the most frequent outcome of the experiment? B. What was the least frequent? C. How many times did we observe a five? D. How many more fours were observed than twos? E. Determine the percentage of time of five was observed. F. Describe the shape of the distribution

A. Seven, it shows the highest frequency. B. Two, it shows the lowest frequency on the Y axis C. 10 times according to the frequency on the Y axis D. 6 because the frequency of four is eight, and the frequency of two is two. So 8-2 = 6 E. 10 times. Because we know that the pair of dice was rolled 100 times. We go to the X axis and see that forfive, the frequency is 10. Be careful on the X axis. F. Bell shaped. Be careful here because it looks like it is skewing left because of the tail. But it's not

The data to the right represents the top speed of all players in a certain soccer league. A. What is the number of classes? B. The lower class limits for the third class? B. The upper class limit for the third class C. The class width

A. There are six classes B. The lower class limit for the third class is 18, because it's the smallest number in the class B. The upper class limit for the third class is 21.9 C. The class with is for because the first class lower limit is 10, and the second class lower limit is 14. So the difference is 4

What do you call the difference between consecutive lower class limits?

Class width

Why shouldn't classes overlap when summarizing continuous data in a frequency or relative frequency distribution?

Classes should not overlap so there is no confusion as to which class and observation belongs If classes overlap, there would be confusion. For example, with a first class of 20 to 30 and a second class of 30 to 40, there would be confusion as to which class and observation of 30 belongs. This could also lead to an observation such as 30 being included in both classes, which would lead to a distribution that doesn't accurately describe the data

The following data shows ages of award-winning male actors at the time they won their award. Make a frequency table for the data using these bins.

Count the number of actors between the ages of 20 and 29, insert. Do the rest for the other classes

True or false: in a frequency distribution, the class with is the distance between the lower and upper limits of a class.

False. In a frequency distribution, the class width Is the distance between either the lower limits of consecutive classes, or the upper limits of consecutive classes

True or false: the shape of the distribution shown is classified as skewed left?

False. The graph actually skews right, because that's where the tail is. You skewer a tail

True or false: the shape of the distribution shown is classified as uniform.

False. This graph is actually symmetric. For a uniform graph, or uniform distribution, all of the bars must be approximately the same height. Here in the symmetric distribution, the highest frequency is in the middle and the frequency's tale to the left and right in a symmetric way

A 2 pound bag of assorted candy contains 100 caramels, 83 mint patties, 93 chocolate squares, 80 net clusters, and 79 peanut butter taffy pieces. To create a pie chart of this data, the angle for the slice representing each candy type must be computed. What is the degree measure of the slice representing the mint patties rounded to the nearest degree?

Here, you have to total up how many candy pieces there are. 435 pieces of candy. Then you need to get the percent that the mint patties are of the total candies, which is 19%. But you need to compute that into a pie chart. So, 19 is to 100, as what number is two 360°? The answer is 68.4.

After constructing a relative frequency distribution summarizing IQ scores of college students, what should the sum of the relative frequencies be?

If percentages are used the sum Should be 100%. If proportions are used the sum should be one.

The following table shows grades for term paper in an English class. The table is incomplete. Complete the table

If the frequency is 50 total, and the relative frequency is 100%. If the frequency of Waze is 12, then the relative frequency is 24%. If you were given the relative frequency and need to do the equation backwards, then you multiply .32 times 50 to find the actual frequency.

What is the difference between relative frequency and cumulative frequency?

Relative frequency of a class is the percentage of the data that falls in that class. Cumulative frequency of a class is the sum of the frequencies of that class and all previous classes

A frequency table of grades has five classes, aBCDF, with frequencies of 3, 13, 13, 5, and three respectively. What are the corresponding cumulative frequencies of the five classes?

The corresponding cumulative frequency's are the running total of every class. Because the first class was three, that cumulative frequency is three. But the second class is 13, so you add 13+3 together to make 16. And you do the rest for the same

Describe the shape of the distribution

The distribution is skewed to the left, because that's where the Tail is

What kind of class limit is the smallest value within the class

The lower class limit

Describe how continuous data are organized in tables. How is the data categorized or grouped When you have intervals of numbers?

The lower class limit is the smallest value within the class, and the upper class limit is the largest value within the class. The class with is the difference between consecutive lower class limits

What kind of class limit is the largest value within the class

The upper class limit