Question

mean of 10 observations is 42. if each observation in data is decreased by 12,what will be the new mean of data.

Answer 1

Mean=sum of total observation /total number of observation
42=sum of total observation /10
420=sum of total observation
Now each member of the observation is decreased 12
=12*10=120
New sum of total observation =420-120
=300
New mean =300/10
=30

OR

SHORT FORMULA
NEW MEAN =MEAN - THE COMMEN NUMBER DECREASED
=40-12
=30

Answer 2

Answer:

Mean= Sum of all observation /No.. of all observation

Step-by-step explanation:

The new mean of the data is 30