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Questions
The following frequency distribution table shows marks obtained by 180 students in Mathematics examination.
| Marks | No. of students |
| 0 - 10 | 25 |
| 10 - 20 | x |
| 20 - 30 | 30 |
| 30 - 40 | 2x |
| 40 - 50 | 65 |
Find the value of x. Also draw a histogram representing the above information.
The following table shows the marks of 180 students in Mathematics.
| Marks | No. of students |
| 0 - 10 | 25 |
| 10 - 20 | x |
| 20 - 30 | 30 |
| 30 - 40 | 2x |
| 40 - 50 | 65 |
Find the value of ‘x’ and draw a histogram.
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Solution
The given table shows marks of 180 students in Mathematics.
25 + x + 30 + 2x + 65 = 180
3x + 120 = 180
3x = 180 − 120
3x = 60
x = `60/3`
x = 20
| Marks | No. of students |
| 0 - 10 | 25 |
| 10 - 20 | 20 |
| 20 - 30 | 30 |
| 30 - 40 | 40 |
| 40 - 50 | 65 |
| Total | 180 |
RELATED QUESTIONS
The marks scored by students in Mathematics in a certain Examination are given below:
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| 0 — 20 | 3 |
| 20 — 40 | 8 |
| 40 — 60 | 19 |
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Construct a frequency polygon without using a histogram for the following frequency distribution :
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The marks scored by students in Mathematics in a certain examination are given below :
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| 0 - 20 | 6 |
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Draw histogram for the above data.
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Represent the following data by histogram:
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Try yourself
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