Question

The mean marks scored by 50 students are 80.On verification of data, it was found that the marks of one student were shown as 73 instead of 37.If corrected, find the new mean.

Answer 1

Mean marks = total marks/ number of students

hence total marks= no. of students x mean marks

The total marks in the first instance= 50 x 80 =  4000

if one student had 37 instead of 73
then the the addition in total marks =  73-37
                                                        =  36

therefore the total marks will be 4000 + 36 = 4036
 mean = total marks/ no. of students
           = 4036/50
           =80.72
New mean= 80.72