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Question
If the arithmetic mean of 8, 4, x, 6, 2, 7 is 5, then the value of x is ______.
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Solution
If the arithmetic mean of 8, 4, x, 6, 2, 7 is 5, then the value of x is 3.
Explanation:
We know that,
Mean = `"Sum of all observations"/"Total number of observations"`
⇒ `5 = (8 + 4 + x + 6 + 2 + 7)/6` ...[∵ Mean = 5, given]
⇒ 30 = 27 + x
⇒ 30 – 27 = x
⇒ 3 = x
∴ x = 3
Hence, the value of x is 3.
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