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Question
If the arithmetic mean of x, x + 3, x + 6, x + 9, and x + 12 is 10, the x =
Options
1
2
6
4
Solution
The given observations are x, x + 3, x + 6, x + 9, and x + 12.
\[\therefore \sum_{}x = 5x + 30, n = 5,\]`overlineX = 10`
Now,
`overlineX =( sumx)/n `
`10 = (5x + 30)/5`
`50 = 5x +30`
`5x = 20`
`x = 4`
Hence, the correct option is (d).
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