Q10 of 48 Page 125

The mean of 5 observations is 50. One of the observations was removed from the data, hence the mean became 45. Find the observation which was removed.

We know that



⇒ Sum of observations = Mean ×Total number of observations


Sum of 5 observations = 50×5=250


Sum after removing one observation = 4×45=180


⇒ Removed observation = sum of 5 observations – Sum after removing one observation


⇒ Removed observation = 250 -180 =70


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