xˉ=87+8+9+7+8+7+λ+8=8⇒854+λ=8⇒λ=10 Now variance =σ2 (7−8)2+(8−8)2+(9−8)2+(7−8)2+(8−8)2=8+(7−8)2+(10−8)2+(8−8)2⇒σ2=81+0+1+1+0+1+4+0=88=1 Hence, the variance is 1 .
If the mean of the data: 7,8,9,7,8,7,λ,8 is 8 , then the variance of this data is
Held on 15 Apr 2018 · Verified 6 Jul 2026.
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