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प्रश्न
The mean of 1, 3, 4, 5, 7, 4 is m. The numbers 3, 2, 2, 4, 3, 3, p have mean m − 1 and median q. Then, p + q =
विकल्प
4
5
6
7
उत्तर
`1,3,4,5,7,4`
Mean`=(1+3+4+5+7+4)/6`
`= 24/6`
`=4`
`M = 4`
Consider the numbers 3, 2, 2, 4, 3, 3, p.
Mean = \[\frac{3 + 2 + 3 + 4 + 3 + 3 + p}{7}\]
\[\Rightarrow 7 \times \left( 4 - 1 \right) = 17 + p\]
\[ \Rightarrow 21 = 17 + p\]
\[ \Rightarrow p = 4\]
Arranging the numbers 3, 2, 2, 4, 3, 3, 4 in ascending order, we have
2, 2, 3, 3, 3, 4, 4
Median`= ((n+1)/2)^(th)`term
`q = ((7-1)/2)^(th)` term
`=(8/2)^(th)`
`=4^(th)` term
∴ q = 3
So,
p+q = 4 +3
= 7
Hence, the correct option is (d).
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