2021 · Q5
The marks obtained by 5 students are 21, 27, 19, 26, 32. Later on 5 grace marks are added to each student. What are the average marks of the revised marks of the students?
Elementary MathematicsStatistics
- A26
- B30
- C31
- D32
Explanation
The original sum is 21 + 27 + 19 + 26 + 32 = 125, so the mean is 125/5 = 25. Adding 5 grace marks to every student shifts each observation by 5, so the mean shifts by exactly 5 as well: 25 + 5 = 30. Hence option B.