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Question
The number of Science and Mathematics projects submitted by Model high school, Nandpur in last 20 years at the state level science exibition is:
2, 3, 4, 1, 2, 3, 1, 5, 4, 2, 3, 1, 3, 5, 4, 3, 2, 2, 3, 2. Prepare a frequency table and find the mean of the data.
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Solution
The frequency table of the data is as follows:
| Number of projects `bb((x_i))` | Frequency `bb((f_i))` | `bb(f_ix_i)` |
| 1 | 3 | 1 x 3 = 3 |
| 2 | 6 | 2 x 6 = 12 |
| 3 | 6 | 3 x 6 = 18 |
| 4 | 3 | 4 x 3 = 12 |
| 5 | 2 | 5 x 2 = 10 |
| ∑f = 20 | `sum f_ix_i` = 55 |
Since the mean of the data = `(sum f_ix_i)/(sumf)"`
`= 55/20`
= 2.75
Hence, the mean of the data is 2.75.
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