The average test score of a class was 58 marks. After four students who scored an average marks of 92 marks transferred out of the class, the average score of the remaining students became 54 marks. How many students were there in the class at first?
| |
(1) |
(2) |
| Number |
1 u |
1 u - 4 |
| Value |
58 |
54 |
| Total value |
58 u |
54 u - 216 |
Number of students at first = 1 u
Total score at first
= 1 u x 58
= 58 u
Total score of the 4 students
= 4 x 92
= 368
Total marks scored after 4 students transferred out
= 54 x (1 u - 4)
= 54 u - 216
58 u - 368 = 54 u - 216
58 u - 54 u = 368 - 216
4 u = 152
1 u = 152 ÷ 4 = 38
Number of students in the class at first
= 1 u
= 38
Answer(s): 38
