Question

A student obtained the mean of 100 observations as 40. It was later found that he had wrongly
copied an observation is 50, the correct figure being 40. Calculate correct mean​

Answer 1

Answer:

solution

Mean of 100 observations =40

Sum of 100 observation = total observation× mean= 100×40 = 4000

Correct sum of 100 no. = 4000-50+40= 3990

Correct mean= sum of observation÷no.of observation=3990÷100= 39.9

HOPE IT HELPS!