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
Represent the following data by Histogram:
|
Price of Sugar per kg (in Rs.) |
Number of Weeks |
| 18-20 | 4 |
| 20-22 | 8 |
| 22-24 | 22 |
| 24-26 | 12 |
| 26-28 | 8 |
| 28-30 | 6 |
Draw a histogram of the following data:
| Class interval: | 10−15 | 15−20 | 20−25 | 25−30 | 30−35 | 34−40 |
| Frequency: | 30 | 98 | 80 | 58 | 29 | 50 |
Draw a histogram for the daily earnings of 30 drug stores in the following table:
| Daily earnings (in Rs): | 450−500 | 500−550 | 550−600 | 600−650 | 650−700 |
| Numbers of stores: | 16 | 10 | 7 | 3 | 1 |
Draw the Histogram and hence, the frequency polygon for the following frequency distribution:
| House Rent (In ₹ per month) | 400-600 | 600-800 | 800-1000 | 1000-1200 |
| Number of families | 200 | 240 | 300 | 50 |
Identify the following data can be represented in a histogram?
Production of cycles in different years
In a village, there are 570 people who have cell phones. An NGO survey their cell phone usage. Based on this survey a histogram is drawn
Are people using cell phone for less than 1 hour?
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 |
Try yourself
- Next time when you watch your favourite TV programme, count the number of advertisements during each break. Use tally marks. Put a dot below the tally when you find children in any advertisement.
- Compare with your friends. Do you get different answers?
The table given below shows the runs scored by a cricket team during the overs of a match.
| Overs | Runs scored |
| 20 – 30 | 37 |
| 30 – 40 | 45 |
| 40 – 50 | 40 |
| 50 – 60 | 60 |
| 60 – 70 | 51 |
| 70 – 80 | 35 |
Use graph sheet for this question.
Take 2 cm = 10 overs along one axis and 2 cm = 10 runs along the other axis.
- Draw a histogram representing the above distribution.
- Estimate the modal runs scored.
