The average amount of money collected by a group of students at a flag day event was $113. When another 14 students turned up to help, the total amount donated increased by $546 and the average amount of money collected became $85. 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 |
113 |
85 |
Total Value |
113 u + 546 |
85 u + 1190 |
Number of students at first = 1 u
Total amount collected by the students at first
= 1 u x 113
= 113 u
Total amount collected by the students in the end
= 85 x (1 u + 14)
= 85 u + 1190
113 u + 546 = 85 u + 1190
113 u - 85 u = 1190 - 546
28 u = 644
1 u = 644 ÷ 28 = 23
Number of students at first
= 1 u
= 23
Answer(s): 23