Advertisements
Advertisements
Question
If Σfi = 25 and Σfixi = 100, then find the mean (`bar"x"`)
Solution
Mean `bar"x" = (Σ"f")/(Σ"fx") = 100/25`
Mean (`bar"x"`) = 4
APPEARS IN
RELATED QUESTIONS
In a retail market, fruit vendors were selling mangoes kept in packing boxes. These boxes contained varying number of mangoes. The following was the distribution of mangoes according to the number of boxes.
| Number of mangoe | 50 − 52 | 53 − 55 | 56 − 58 | 59 − 61 | 62 − 64 |
| Number of boxes | 15 | 110 | 135 | 115 | 25 |
Find the mean number of mangoes kept in a packing box. Which method of finding the mean did you choose?
If the mean of the following data is 20.6. Find the value of p.
| x | 10 | 15 | P | 25 | 35 |
| f | 3 | 10 | 25 | 7 | 5 |
Find the value of p, if the mean of the following distribution is 20.
| x | 15 | 17 | 19 | 20+P | 23 |
| f | 2 | 3 | 4 | 5P | 6 |
The following table gives the number of boys of a particular age in a class of 40 students. Calculate the mean age of the students
| Age (in years) | 15 | 16 | 17 | 18 | 19 | 20 |
| No. of students | 3 | 8 | 10 | 10 | 5 | 4 |
The following distribution gives the number of accidents met by 160 workers in a factory during a month.
| No. of accidents(x) | 0 | 1 | 2 | 3 | 4 |
| No. of workers (f) | 70 | 52 | 34 | 3 | 1 |
Find the average number of accidents per worker.
If the mean of the following frequency distribution is 24, find the value of p.
| Class | 0-10 | 10-20 | 20-30 | 30-40 | 40-50 |
| Frequency | 3 | 4 | p | 3 | 2 |
Find the mean of the following frequency distribution, using the assumed-mean method:
| Class | 100 – 120 | 120 – 140 | 140 – 160 | 160 – 180 | 180 – 200 |
| Frequency | 10 | 20 | 30 | 15 | 5 |
If the arithmetic mean, 7, 8, x, 11, 14 is x, then x =
The weekly wages of 120 workers in a factory are shown in the following frequency distribution table. Find the mean of the weekly wages.
|
Weekly wages
(Rupees)
|
0 - 2000 | 2000 - 4000 | 4000 - 6000 | 6000 - 8000 |
| No. of workers | 15 | 35 | 50 | 20 |
Find the mean of the following distribution:
| x | 4 | 6 | 9 | 10 | 15 |
| f | 5 | 10 | 10 | 7 | 8 |
The mean of the following distribution is 6. Find the value at P:
| x | 2 | 4 | 6 | 10 | P + 5 |
| f | 3 | 2 | 3 | 1 | 2 |
The following table gives the wages of worker in a factory:
| Wages in ₹ | 45 - 50 | 50 - 55 | 55 - 60 | 60 - 65 | 65 - 70 | 70 - 75 | 75 - 80 |
| No. of Worker's | 5 | 8 | 30 | 25 | 14 | 12 | 6 |
Calculate the mean by the short cut method.
If the arithmetic mean of x, x + 3, x + 6, x + 9 and x + 12 is 10, then x = ?
The formula for finding mean by direct method is `(sum(AxxB))/(sumA)` where B and A are respectively.
In the formula `barx = a + h((sumf_iu_i)/(sumf_i))`, for finding the mean of grouped frequency distribution, ui = ______.
Calculate the mean of the scores of 20 students in a mathematics test:
| Marks | 10 – 20 | 20 – 30 | 30 – 40 | 40 – 50 | 50 – 60 |
| Number of students |
2 | 4 | 7 | 6 | 1 |
Find the mean for the following distribution:
| Class Interval | 20 - 40 | 40 - 60 | 60 - 80 | 80 - 100 |
| Frequency | 4 | 7 | 6 | 3 |
Find the mean of the following data using assumed mean method:
| Class | 0 – 5 | 5 – 10 | 10 – 15 | 15 – 20 | 20 – 25 |
| Frequency | 8 | 7 | 10 | 13 | 12 |
