The average amount of money collected by a group of students at a flag day event was $102. When another 12 students turned up to help, the total amount donated increased by $540 and the average amount of money collected became $83. 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 |
102 |
83 |
Total Value |
102 u + 540 |
83 u + 996 |
Number of students at first = 1 u
Total amount collected by the students at first
= 1 u x 102
= 102 u
Total amount collected by the students in the end
= 83 x (1 u + 12)
= 83 u + 996
102 u + 540 = 83 u + 996
102 u - 83 u = 996 - 540
19 u = 456
1 u = 456 ÷ 19 = 24
Number of students at first
= 1 u
= 24
Answer(s): 24