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प्रश्न
If the mean of 6, 7, x, 8, y, 14 is 9, then ______.
विकल्प
x + y = 21
x + y = 19
x − y = 19
x − y = 21
उत्तर
If the mean of 6, 7, x, 8, y, 14 is 9, then x + y = 19.
Explanation:
The given observations are 6, 7, x, 8, y, 14.
Mean = 9 ...(Given)
\[\Rightarrow \frac{6 + 7 + x + 8 + y + 14}{6} = 9\]
\[\Rightarrow 35 + x + y = 54\]
\[\Rightarrow x + y = 54 - 35 = 19\]
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