Advertisements
Advertisements
Question
The distribution given below shows the runs scored by batsmen in one-day cricket matches. Find the mean number of runs.
| Runs scored |
0 – 40 | 40 – 80 | 80 – 120 | 120 – 160 | 160 – 200 |
| Number of batsmen |
12 | 20 | 35 | 30 | 23 |
Solution
| Runs scored | 0 – 40 | 40 – 80 | 80 – 120 | 120 – 160 | 160 – 200 | Total |
| Number of batsmen `(f_i)` |
12 | 20 | 35 | 30 | 23 | 120 |
| `x_i` | 20 | 60 | 100 | 140 | 180 | |
| `f_ix_i` | 240 | 1200 | 3500 | 4200 | 4140 | 13280 |
Mean `(barx) = (sumf_ix_i)/(sumf_i) = 13280/120` = 110.67 runs
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?
The arithmetic mean of the following data is 25, find the value of k.
| x1 | 5 | 15 | 25 | 35 | 45 |
| f1 | 3 | k | 3 | 6 | 2 |
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.
The mean of the following frequency distribution is 62.8 and the sum of all the frequencies is 50. Compute the missing frequency f1 and f2.
| Class | 0 - 20 | 20 - 40 | 40 - 60 | 60 - 80 | 80 - 100 | 100 - 120 |
| Frequency | 5 | f1 | 10 | f2 | 7 | 8 |
The loans sanctioned by a bank for construction of farm ponds are shown in the following table. Find the mean of the loans.
|
Loan
(Thousand Rupees)
|
40 - 50 | 50 - 60 | 60 - 70 | 70 - 80 | 80 - 90 |
| No. of farm ponds | 13 | 20 | 24 | 36 | 7 |
Find the mean of the following distribution:
| Class interval | 0 - 10 | 10 - 20 | 20 - 30 | 30 - 40 | 40 - 50 |
| Frequency | 10 | 6 | 8 | 12 | 5 |
The average weight of a group of 25 men was calculated to be 78.4 kg. It was discovered later that one weight was wrongly entered as 69 kg instead of 96 kg. What is the correct average?
In the formula `barx = a + (f_i d_i)/f_i`, for finding the mean of grouped data di’s are deviations from a of ______.
In calculating the mean of grouped data, grouped in classes of equal width, we may use the formula `barx = a + (sumf_i d_i)/(sumf_i)` where a is the assumed mean. a must be one of the mid-points of the classes. Is the last statement correct? Justify your answer.
Find the mean for the following distribution:
| Class Interval | 20 - 40 | 40 - 60 | 60 - 80 | 80 - 100 |
| Frequency | 4 | 7 | 6 | 3 |
