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Question
The following is the record of goals scored by team A in a football session:
|
No. of goals scored |
0 |
1 |
2 |
3 |
4 |
|
No. of matches |
1 |
9 |
7 |
5 |
3 |
For the team B, mean number of goals scored per match was 2 with a standard deviation 1.25 goals. Find which team may be considered more consistent?
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Solution
The mean and the standard deviation of goals scored by team A are calculated as follows.
| No. of goals scored | No. of matches | fixi | xi2 | fixi2 |
|
0 |
1 |
0 |
0 |
0 |
|
1 |
9 |
9 |
1 |
9 |
|
2 |
7 |
14 |
4 |
28 |
|
3 |
5 |
15 |
9 |
45 |
|
4 |
3 |
12 |
16 |
48 |
|
25 |
50 |
130 |
The standard deviation of team B is 1.25 goals.
The average number of goals scored by both the teams is same i.e., 2. Therefore, the team with lower standard deviation will be more consistent.
Thus, team A is more consistent than team B
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