The average amount of money collected by a group of students at a flag day event was $103. When another 13 students turned up to help, the total amount donated increased by $595 and the average amount of money collected became $72. How many students were there in the group in the end?
|
Number of students at first |
Number of students in the end |
Number |
1 u |
1 u + 13 |
Value |
103 |
72 |
Total Value |
103 u + 595 |
72 u + 936 |
Number of students at first = 1 u
Total amount collected by the students at first
= 1 u x 103
= 103 u
Total amount collected by the students in the end
= 72 x (1 u + 13)
= 72 u + 936
103 u + 595 = 72 u + 936
103 u - 72 u = 936 - 595
31 u = 341
1 u = 341 ÷ 31 = 11
Number of students in the end
= 1 u + 13
= 11 + 13
= 24
Answer(s): 24