Question

7. The mean of 5 observations is 38. If one observation is excluded, the mean becomes 35. What is the excluded number?

Answer 1

Answer:

Excluded observation = 50

Step-by-step explanation:

Given:

• Mean of 5 observations = 38
• If one observation is excluded, Mean of 4 observations (5 observations - excluded observation) = 35

Mean:

Mean is simply defined as average of observations

Mean = Sum of all observations / Total observations

Solution:

Let sum of 5 observations be S

Mean of 5 observations = 38

=> S/5 = 38

=> S = 38*5 = 190

S = 190

Let the excluded observation be 'n'

New sum of observations = S - n = 190 - n

Mean of 4 observations = 35

=> (190 - n)/4 = 35

=> 190 - n = 35*4

=> 190 - n = 140

=> n = 190 - 140

=> n = 50

n = 50