Question

The mean of 20 observation is 15bon checking iy was found that the observation were copied as 3 and 6 if wrong observation are replaced by their correct values 8 and 4., then the correct mean is​

Answer 1

Answer:

15.15

Step-by-step explanation:

we find the sum of all the observations by multiplying 20 and the mean i.e. 15.

if the observation of 3 is replaces with the observation of 8 that means, the sum would be incremented by 5  and similarly, in the case that the observation 6 is replaced by 4 the sum would be decremented by 2 leading us to the final sum of 303. therefore, the mean would be 303/20 = 15.15