Let 5 th observation be x. Given mean =7 ∴7=56+7+8+10+x⇒x=4 Now, Variance =5(6−7)2+(7−7)2+(8−7)2+(10−7)2+(4−7)2=512+02+12+32+32=520=4=2
Mean of 5 observations is 7 . If four of these observations are 6,7,8,10 and one is missing then the variance of all the five observations is :
Held on 22 Apr 2013 · Verified 6 Jul 2026.
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