The average amount of money collected by a group of students at a flag day event was $116. When another 14 students turned up to help, the total amount donated increased by $634 and the average amount of money collected became $86. 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 + 14 |
Value |
116 |
86 |
Total Value |
116 u + 634 |
86 u + 1204 |
Number of students at first = 1 u
Total amount collected by the students at first
= 1 u x 116
= 116 u
Total amount collected by the students in the end
= 86 x (1 u + 14)
= 86 u + 1204
116 u + 634 = 86 u + 1204
116 u - 86 u = 1204 - 634
30 u = 570
1 u = 570 ÷ 30 = 19
Number of students at first
= 1 u
= 19
Answer(s): 19