Advertisements
Advertisements
Question
Find the class boundaries and class marks of the following classes:
55 - 59, 60 - 64, 65 - 69, 70 - 74, 75 - 79, 80 - 84, 85 - 89, 90 - 94 and 95 - 99.
Advertisements
Solution
For the class 55 - 59,
The actual lower limit = 55 - 0.5 = 54.5
The actual upper limit = 59 + 0.5 = 59.5
∴ The class boundaries are 54.5 and 59.5
∴ The class mark = `(1)/(2)(54.5 + 59.5)` = 57
Similarly calculating for the other classes we get the following table:
| Class | Class Boundaries | Class Mark |
| 55 - 59 | 54.5 - 59.5 | 57 |
| 60 - 64 | 59.5 - 64.5 | 62 |
| 65 - 69 | 64.5 - 69.5 | 67 |
| 70 - 74 | 69.5 - 74.5 | 72 |
| 75 - 79 | 74.5 - 79.5 | 77 |
| 80 - 84 | 79.5 - 84.5 | 82 |
| 85 - 89 | 84.5 - 89.5 | 87 |
| 90 - 94 | 89.5 - 94.5 | 92 |
| 95 - 99 | 94.5 - 99.5 | 97 |
APPEARS IN
RELATED QUESTIONS
Find the actual lower and upper-class limits and also the class marks of the classes:
1.1 - 2.0, 2.1 -3.0 and 3.1 - 4.0.
Find the actual lower class limits, upper-class limits and the mid-values of the classes:
10 - 19, 20 - 29, 30 - 39 and 40 - 49.
Fill in the blank :
The class mark of class interval 22 - 29 is ...........
Fill in the blank:
Lower class limit of 15-18 is ………
Fill in the blank:
The upper limit of 5-12.5 is ………
Fill in the blank:
If the upper and the lower limits of a class interval are 16 and 10; the class-interval is ……..
Fill in the blank:
If the lower and the upper limits of a class interval are 7.5 and 12.5; the class interval is ……..
The number of goals scored by Arsenal Football Club in the English Premier League in the season 2007 were:
1, 2, 1, 3, 2, 5, 1, 6, 4, 4, 2, 3, 5, 6, 4, 2, 2, 3, 4, 1, 0, 5, 0, 5, 3, 2, 3, 4, 4, 1, 1, 2, 4, 3. 1. 4
Arrange these data in a distance frequency distribution table and answer the following:
(i) What is the range of the number of goals scored by AFC?
(ii) How many times did AFC score 3 or more than 3 goals?
(iii) Which variatie has the highest frequency?
If the class intervals of a frequency distribution are 5 - 12, 13 - 20, 21 - 28, 29 - 36, 37 - 44, 45 - 52 and 53 - 60, find the following:
(i) The class limits and class boundaries of 21 - 28
(ii) The class size and the class mark of the class interval 45 - 52.
(iii) Find the true class limits of all the class intervals.
The class marks of a frequency distribution are: 15, 25, 35, 45, 55, 65 and 75. Determine the class limits.
