The average amount of money collected by a group of students at a flag day event was $105. When another 11 students turned up to help, the total amount donated increased by $628 and the average amount of money collected became $88. 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 + 11 |
Value |
105 |
88 |
Total Value |
105 u + 628 |
88 u + 968 |
Number of students at first = 1 u
Total amount collected by the students at first
= 1 u x 105
= 105 u
Total amount collected by the students in the end
= 88 x (1 u + 11)
= 88 u + 968
105 u + 628 = 88 u + 968
105 u - 88 u = 968 - 628
17 u = 340
1 u = 340 ÷ 17 = 20
Number of students in the end
= 1 u + 11
= 20 + 11
= 31
Answer(s): 31