Page 2 - CH-15(XI) WORKSHEETS. (2)
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10. Calculate the mean deviation from the median for the following data.
Wages Per Day. Number of worker.
20 – 30 3
30 - 40 8
40 – 50 12
50 – 60 9
60 – 70 8
11. The mean & SD of 20 observation are found to be 10 & 2 respectively, on rechecking it
was found an observation 8 was incorrect , Calculate the correct mean & SD. In each of
following case (a) If wrong item was omitted (b) It is replaced by 12
