Question

 Here is a data set summarized as a stem-and-leaf plot: 

5#| 13355568 

6#| 002234444555777 

7#| 04578 

8#1 125 

How many data values are in this data set? 

What is the minimum value in the last class? 

What is the frequency of the modal class? (Hint, That is the frequency of the class with the most data points in it.) 

How many of the original values are greater than 70? 

Answer 1

Data points are

In the first row:

51,53,53,55,55,55,56,58

Second row:

60,60,62,62,63,64,64,64,64,65,65,65,67,67,67

Third row:

70,74,75,77,78

Fourth row:

81,82,85

a)

Total there are 31 data points

51,53,53,55,55,55,56,58,60,60,62,62,63,64,64,64,64,65,65,65,67,67,67,70,74,75,77,78,81,82,85

b)

Minimum value in the last class i.e. fourth row is 81

c)

Frequency of modal class.

The mode of a set of data values is the value that appears most often.

Here second row has largest number of data points so second row is modal class.

Frequency of modal class is 15

d)

Values that are greater than 70 are

74, 75, 77, 78, 81, 82, 85

So total 7 values.