Advertisements
Advertisements
प्रश्न
The median of the following frequency distribution is 25. Find the value of x.
| Class: | 0 – 10 | 10 – 20 | 20 – 30 | 30 – 40 | 40 – 50 |
| Frequency: | 6 | 9 | 10 | 8 | x |
उत्तर
| Class Interval | Frequency | Cumulative frequency (`"C"_f`) |
| 0 – 10 | 6 | 6 |
| 10 – 20 | 9 | 15 |
| 20 – 30 | 10 | 25 |
| 30 – 40 | 8 | 33 |
| 40 – 50 | x | 33 + x |
| `sumf_i` = 33 + x |
Total frequency = 33 + x
i.e., N = 33 + x
∴ `"N"/2 = (33 + x)/2`
Median = 25
So class corresponding to this 20 – 30,
So, l = 20, `"C"_f` = 15, `f` = 10 and h = 10
Median = `"l" + (("N"/2 - "c"_f)/f) xx "h"`
⇒ 25 = `20 + (((33 + x)/2 - 15)/10) xx 10`
⇒ 25 = `20 + (33 + x - 30)/2` ...[Given, Median = 25]
⇒ 25 – 20 = `(3 + x)/2`
⇒ 10 = 3 + x
⇒ x = 7
APPEARS IN
संबंधित प्रश्न
The following is the distribution of the size of certain farms from a taluka (tehasil):
| Size of Farms (in acres) |
Number of Farms |
| 5 – 15 | 7 |
| 15 – 25 | 12 |
| 25 – 35 | 17 |
| 35 – 45 | 25 |
| 45 – 55 | 31 |
| 55 – 65 | 5 |
| 65 – 75 | 3 |
Find median size of farms.
Calculate the missing frequency from the following distribution, it being given that the median of the distribution is 24.
| Age in years | 0 - 10 | 10 - 20 | 20 - 30 | 30 - 40 | 40 - 50 |
| No. of persons | 5 | 25 | ? | 18 | 7 |
If the median of the following frequency distribution is 32.5, find the values of `f_1 and f_2`.
| Class | 0 – 10 | 10 – 20 | 20 – 30 | 30 -40 | 40 – 50 | 50 – 60 | 60 – 70 | Total |
| Frequency | `f_1` |
5 |
9 | 12 | `f_2` | 3 | 2 | 40 |
If the mean of the following distribution is 3, find the value of p.
| x | 1 | 2 | 3 | 5 | p + 4 |
| f | 9 | 6 | 9 | 3 | 6 |
The prices of different articles and demand for them is shown in the following frequency distribution table. Find the median of the prices.
|
Price (Rupees)
|
20 less than | 20 – 40 | 40 – 60 | 60 – 80 | 80 – 100 |
| No. of articles | 140 | 100 | 80 | 60 | 20 |
Calculate the median of the following distribution:
| Weight (in nearest kg.) | No. of students |
| 46 | 7 |
| 48 | 5 |
| 50 | 8 |
| 52 | 12 |
| 53 | 10 |
| 54 | 2 |
| 55 | 1 |
The abscissa of the point of intersection of the less than type and of the more than type cumulative frequency curves of a grouped data gives its ______.
The maximum speeds, in km per hour, of 35 cars in a race are given as follows:
| Speed (km/h) | 85 – 100 | 100 – 115 | 115 – 130 | 130 – 145 |
| Number of cars | 5 | 8 | 13 | 9 |
Calculate the median speed.
The median of the following frequency distribution is 35. Find the value of x.
| Class: | 0 – 10 | 10 – 20 | 20 – 30 | 30 – 40 | 40 – 50 |
| Frequency: | 6 | 3 | x | 12 | 19 |
Find the modal and median classes of the following distribution.
| Class | 0 – 20 | 20 – 40 | 40 – 60 | 60 – 80 | 80 – 100 |
| Frequency | 11 | 22 | 19 | 18 | 7 |
