Question

Ch- Data handling
The mean of five observation is 17.If the mean of first three observation is 15 and rest three is 18, then find the third observation.

Answer 1

mean of five observation =17
sum of the five observation = 17*5 = 85
mean of first three observation = 15
sum of the first three observation = 15*3 = 45
mean of last three observation = 18
sum of the last three observation  = 18*3 =54

since,the third observation occurs twice.
the third observation = 45+54-85
                                   ⇒99-85
                                   ⇒14
i think this will help u!!!!!!!!