Question

the mean of 13 observation is 14.the mean of first seven observations is 12 ..the mean of last seven observations is 16. find the seventh observations .

Answer 1

Mean of 13 observations= 14
sum of 13 observations = 13*14= 182

Mean of first 7 observations = 12
sum of first 7 observations = 7*12= 84

Mean of last 7 observations = 16
sum of last 7 observations = 7*16= 112

the 7th observation = 112- 84 = 28

Answer 2

Answer:

14

Step-by-step explanation

Let the 7th observation be p.

Now, Sum of 13 observation = 13 × 14 = 182.

Sum of first 7 observation = 12 × 7 = 84.

Sum of last 7 observation = 16 × 7 = 112.

Sum of last 6 observation = 112 - p.

Sum of 13 observation = Sum of first 7 observation + Sum of last 6 observation

= 84 + 112 - p = 196 - p

So, 196 - p = 182 =

p = 196 - 182 = 14.

Thus, the 7th observation is 14