Question

the mean of marks obtained by 15 student is 63 if marks of two students were wrongly 73 instead of 78 and 59 instead of 69 find the correct mean​

Answer 1

Answer =64 Explanation you will multiplare the number of the students by the number of mean marks,then you add the wrong marks subtract from the total marks,then add the correct scores to the main marks.calculation:63×15=945,73+59=132,945-132=813,813+78+69