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CGP EDU Academic Team
Published on: August 14, 2026
In ten observations, the mean of all 10 numbers is 15, the mean of the first six observations is 16 and the mean of the last five observations is 12. The sixth number is
Text Solution
Verified by ExpertsThe correct answer is:
A
6
Let the mean of the last four observations be A 2 . Then, by the formula for combined mean, we get,
or 150=96+4A 2
Let the sixth number is x, then taking the sixth number as a collection, the combined mean of this collection and the collection of the last four is 12.
By the definition of combined mean
Hence, the sixth number = 6
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