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Question
In the following data one of the value of y is missing. Arithmetic means of x and y series are 6 and 8 respectively. `(sqrt(2) = 1.4142)`
| x | 6 | 2 | 10 | 4 | 8 |
| y | 9 | 11 | ? | 8 | 7 |
Estimate missing observation.
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Solution
Let the missing observation be 'a'
| x | 6 | 2 | 10 | 4 | 8 |
| y | 9 | 11 | a | 8 | 7 |
`bar"x"` = 6, `bar"y"` = 8, n = 5
`bar"y" = (sum_"y")/"n"`
∴ 8 = `(35 + "a")/5`
∴ a + 35 = 40
∴ a = 40 − 35
∴ a = 5
∴ Missing frequency = 5
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