Question

The mean of 8 observation was to be 43 later it was discovered that one observation 38 was misread as 83 find the correct mean

Answer 1

correct mean 38

mean of 9 observation = 43

sum of 9 observation = 43 × 9

sum of 9 observation = 387

since 38 misread as 83

Then, sum of new observation =

387 - ( wrong observation)+(correct obser.)

387-83+38

387-45 = 342

correct mean= sum of new observation/total no. of observation

correct mean= 342/9 = 38

hence, correct mean is 38

i hope it will helps you.

best of luck for your exams.!!