Advertisements
Advertisements
प्रश्न
The histogram below represents the scores obtained by 25 students in a mathematics mental test. Use the data to:
- Frame a frequency distribution table.
- To calculate mean.
- To determine the Modal class.
Advertisements
उत्तर
i.
| Class interval | Frequency |
| 0 – 10 | 2 |
| 10 – 20 | 5 |
| 20 – 30 | 8 |
| 30 – 40 | 4 |
| 40 – 50 | 6 |
ii.
| Class interval | Frequency (f) | Mean value (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 |
| `sumf = 25` | `sumf = 695` |
∴ Mean = `(sumfx)/(sumf)`
= `695/25`
= 27.8
iii. Here the maximum frequency is 8 which is corresponding to class 20 – 30.
Hence, the modal class is 20 – 30.
APPEARS IN
संबंधित प्रश्न
For which of these would you use a histogram to show the data?
(a) The number of letters for different areas in a postman’s bag.
(b) The height of competitors in an athletics meet.
(c) The number of cassettes produced by 5 companies.
(d) The number of passengers boarding trains from 7:00 a.m. to 7:00 p.m. at a station.
Give reasons for each.
In the following table, the investment made by 210 families is shown. Present it in the form of a histogram.
|
Investment
(Thousand Rupees) |
10 - 15 | 15 - 20 | 20 - 25 | 25 - 30 | 30 - 35 |
| No. of families | 30 | 50 | 60 | 55 | 15 |
Number of workshops organized by a school in different areas during the last five years are as follows:
| Years | No. of workshops |
| 1995−1996 | 25 |
| 1996−1997 | 30 |
| 1997−1998 | 42 |
| 1998−1999 | 50 |
| 1999−2000 | 65 |
Draw a histogram representing the above data.
Construct histograms for following frequency distribution:
| Class Interval | 110-119 | 120-129 | 130-139 | 140-149 | 150-159 |
| Frequency | 15 | 23 | 30 | 20 | 16 |
Construct histograms for following frequency distribution:
| Class Interval | 1-10 | 11-20 | 21-30 | 31-40 | 41-50 |
| Frequency | 11 | 23 | 30 | 20 | 16 |
Construct a histogram from the following distribution of total marks of 40 students in a class.
| Marks | 90 − 110 | 110 − 130 | 130 − 150 | 150 − 170 | 170 − 190 | 190 − 210 |
| No. of Students | 9 | 5 | 10 | 7 | 4 | 6 |
The graphical representation of grouped data is _________
Draw a histogram for the given frequency distribution
| Age | 41 − 45 | 46 − 50 | 51 − 55 | 56 − 60 | 61 − 65 | 66 − 70 | 71 − 75 |
| Frequency | 4 | 9 | 17 | 25 | 15 | 8 | 2 |
Histogram shows the number of people owning the different number of books. Answer the question based on it.
The number of people owning books more than 60 is ______.
From the histogram given on the right, we can say that 1500 males above the age of 20 are literate.
