Answers

2016-02-19T17:27:40+05:30
Old mean= sum of 50 observations/50
70*50= sum of observations
3500= sum
Now, 85 was wrongly read 60 therefore, we will need to add 15(85-60) to the sum of observations to get correct mean
Therefore, correct mean= (3500+15)/50
= 3515/50
=70.3
Therefore, 70.3 is correct mean
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