The average amount of money collected by a group of students at a flag day event was $112. When another 12 students turned up to help, the total amount donated increased by $648 and the average amount of money collected became $88. How many students were there in the group at first?
| |
Number of students
at first |
Number of students
in the end |
| Number |
1 u |
1 u + 12 |
| Value |
112 |
88 |
| Total Value |
112 u + 648 |
88 u + 1056 |
Number of students at first = 1 u
Total amount collected by the students at first
= 1 u x 112
= 112 u
Total amount collected by the students in the end
= 88 x (1 u + 12)
= 88 u + 1056
112 u + 648 = 88 u + 1056
112 u - 88 u = 1056 - 648
24 u = 408
1 u = 408 ÷ 24 = 17
Number of students at first
= 1 u
= 17
Answer(s): 17
