The average test score of a class was 68 marks. After four students who scored an average marks of 96 marks transferred out of the class, the average score of the remaining students became 52 marks. How many students were there in the class at first?
| |
(1) |
(2) |
| Number |
1 u |
1 u - 4 |
| Value |
68 |
52 |
| Total value |
68 u |
52 u - 208 |
Number of students at first = 1 u
Total score at first
= 1 u x 68
= 68 u
Total score of the 4 students
= 4 x 96
= 384
Total marks scored after 4 students transferred out
= 52 x (1 u - 4)
= 52 u - 208
68 u - 384 = 52 u - 208
68 u - 52 u = 384 - 208
16 u = 176
1 u = 176 ÷ 16 = 11
Number of students in the class at first
= 1 u
= 11
Answer(s): 11
