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Statistics question

2021 · 27 Jul · Shift 2 · Q28
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  5. /2021 · 27 Jul · Shift 2 · Q28

Statistics question

2021 · 27 Jul · Shift 2 · Q28

JEE MainMathematicsStatisticsMCQ+4 / −1
Let the mean and variance of the frequency distribution x:x1=2x2=6x3=8x4=9f:44αβ\begin{matrix} {x:} & {{x_1} = 2} & {{x_2} = 6} & {{x_3} = 8} & {{x_4} = 9} \\ {f:} & 4 & 4 & \alpha & \beta \\ \end{matrix}x:f:​x1​=24​x2​=64​x3​=8α​x4​=9β​ be 6 and 6.8 respectively. If x3 is changed from 8 to 7, then the mean for the new data will be :
  1. A
    4
  2. B
    5
  3. C
    173{{17} \over 3}317​
  4. D
    163{{16} \over 3}316​
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