Question

the mean of the 100 observation is 45 .it was later found that two observations 19 and 31 are incorrectly recorded as 91 and 31 .Find the correct mean​

Answer 1

Answer:

Mean = 45

x/100=45

x= 4500

Two number (91+13)=104 incorrect

Two number (91+13)=104 incorrectSo let sum = 4500 – 104 = 4396

Two number (91+13)=104 incorrectSo let sum = 4500 – 104 = 4396Add correct number 19+31 = 50

= 4396+50 = 4446

Mean = 4446/100

= 44.46

Answer 2

Answer:

Mean = 45

x/100 = 45

x = 4500

Two number (91+13) = 104 incorrect

Two number (91+13) = 104 incorrect.

So let sum = 4500 - 104 = 4396

Add correct number 19+31 = 50

= 4396+50 = 4446

Mean= 4446/100

=44.46