The table shows the distribution of monthly income (in thousands of naira) of workers in a factory
(a) Draw a histogram for the distribution.
(b) Use your graph to estimate the mode of the distribution.
| Monthly Income (N'1000) | 135-139 | 140-149 | 150-154 | 155-164 | 165-169 |
| Number of workers | 20 | 42 | 28 | 38 | 22 |
(a) Draw a histogram for the distribution.
(b) Use your graph to estimate the mode of the distribution.
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Correct Answer: Option
Explanation:
(a)
(b) Modal class: This is the class boundary with the highest frequency.
In this case, it is 139.5 and 149.5.
From the histogram, the modal income is 3 +139.5
= 142.5 or N142500 (in thousands of naira)
| Monthly Income | Number of Workers | Class Boundaries |
| 135-139 | 20 | 134.5 - 139.5 |
| 140-149 | 42 | 139.5 - 149.5 |
| 150-154 | 28 | 149.5 - 154.5 |
| 155-164 | 38 | 154.5 - 164.5 |
| 165-169 | 22 | 164.5 - 169.5 |
(a)
(b) Modal class: This is the class boundary with the highest frequency.
In this case, it is 139.5 and 149.5.
From the histogram, the modal income is 3 +139.5
= 142.5 or N142500 (in thousands of naira)