Mathematics
The histogram below represents the scores obtained by 25 students in a Mathematics mental test. Use the data to :
(i) Frame a frequency distribution table.
(ii) To calculate mean.
(iii) To determine the modal class.
Measures of Central Tendency
12 Likes
Answer
(i) Frequency distribution table :
| Marks (Class) | No. of students (frequency) |
|---|---|
| 0 - 10 | 2 |
| 10 - 20 | 5 |
| 20 - 30 | 8 |
| 30 - 40 | 4 |
| 40 - 50 | 6 |
(ii) Mean
| Marks (Class) | No. of students (frequency) | Class mean (x) | fx |
|---|---|---|---|
| 0 - 10 | 2 | 5 | 10 |
| 10 - 20 | 5 | 15 | 75 |
| 20 - 30 | 8 | 25 | 200 |
| 30 - 40 | 4 | 35 | 140 |
| 40 - 50 | 6 | 45 | 270 |
| Total | Σf = 25 | Σfx = 695 |
By formula,
Mean =
= = 27.8
Hence, mean = 27.8
(iii) From table,
Class 20 - 30 has the highest frequency.
Hence, modal class = 20 - 30.
Answered By
7 Likes
Related Questions
The distribution given below, shows the marks obtained by 25 students in an aptitude test. Find the mean, median and mode of the distribution.
Marks obtained No. of students 5 3 6 9 7 6 8 4 9 2 10 1 The monthly income of a group of 320 employees in a company is given below :
Monthly income No. of employees 6 - 7 20 7 - 8 45 8 - 9 65 9 - 10 95 10 - 11 60 11 - 12 30 12 - 13 5 Draw an ogive of the given distribution on a graph sheet taking 2 cm = ₹ 1000 on one axis and 2 cm = 50 employees on the other axis. From the graph determine :
(i) the median wage.
(ii) the number of employees whose income is below ₹ 8500.
The mean of numbers 45, 52, 60, x, 69, 70, 26, 81 and 94 is 68. Find the value of x. Hence, estimate the median for the resulting data.
The marks of 10 students of a class in an examination arranged in ascending order is as follows :
13, 35, 43, 46, x, x + 4, 55, 61, 71, 80.
If the median marks is 48, find the value of x. Hence, find the mode of the given data.