Advertisements
Advertisements
प्रश्न
Find the mean of each of the following frequency distributions
| Class interval | 0 - 10 | 10 - 20 | 20 - 30 | 30 - 40 | 40 - 50 |
| Frequency | 9 | 12 | 15 | 10 | 14 |
उत्तर
Let the assumed mean A = 25
| Class interval | Mid value(x1) | d1 = x1 - 25 | `"u"_1=(x_1-25)/10` | f1 | f1u1 |
| 0 -10 | 5 | -20 | -2 | 9 | -18 |
| 10 - 20 | 15 | -10 | -1 | 12 | -12 |
| 20 - 30 | 25 | 0 | 0 | 15 | 0 |
| 30 - 40 | 35 | 10 | 1 | 10 | 10 |
| 40 - 50 | 45 | 20 | 2 | 14 | 28 |
| N = 60 | `sumf_1"u"_1=8` |
We have
A = 25, h = 10
Mean `=A+hxx(sumf_1"u"_1)/N`
`=25+10xx8/60`
`=25+80/60`
= 25 + 1.333
= 26.333
APPEARS IN
संबंधित प्रश्न
Find the mean from the following frequency distribution of marks at a test in statistics:
| Marks(x) | 5 | 10 | 15 | 20 | 25 | 30 | 35 | 40 | 45 | 50 |
| No. of students (f) | 15 | 50 | 80 | 76 | 72 | 45 | 39 | 9 | 8 | 6 |
Find the mean of each of the following frequency distributions
| Class interval | 0 - 8 | 8 - 16 | 16 - 24 | 24 - 32 | 32 - 40 |
| Frequency | 5 | 9 | 10 | 8 | 8 |
Find the mean of the following frequency distribution using step-deviation method
| Class | 0 – 10 | 10 – 20 | 20 – 30 | 30 – 40 | 40 – 50 |
| Frequency | 7 | 10 | 15 | 8 | 10 |
If the mean of the following frequency distribution is 18, find the missing frequency.
| Class interval | 11 – 13 | 13 – 15 | 15 – 17 | 17 – 19 | 19 – 21 | 21 – 23 | 23 – 25 |
| Frequency | 3 | 6 | 9 | 13 | f | 5 | 4 |
If the arithmetic mean of x, x + 3, x + 6, x + 9, and x + 12 is 10, the x =
While computing mean of grouped data, we assume that the frequencies are ______.
Find the mean wage of a worker from the following data:
| Wages (In ₹) | 1400 | 1450 | 1500 | 1550 | 1600 | 1650 | 1700 |
| Number of workers | 15 | 20 | 18 | 27 | 15 | 3 | 2 |
Mean of n numbers x1, x2, … xn is m. If xn is replaced by x, then new mean is ______.
| xi | fi | fixi |
| 4 | 10 | A ______ |
| 8 | 11 | B ______ |
| 12 | 9 | C ______ |
| 16 | 13 | D ______ |
| `sumf_ix_i =` ______ |
Find the value of `sumf_ix_i`
(For an arranged data) The median is the ______.
