Question

The average of 12 observations is 8. Later it was observed that one observation 10 is wrongly written as 13. The correct average of observation is.

• A. 7
• B. 17.5
• C. 7.75
• D. 8

Answer 1

Answer:

C. 7.75

Sum of 12 observations = 12x8=96 Correct sum of 12 observations =96-13+10=93 New average of 12 obsrvations = 93/12 =7.75