The average amount of money collected by a group of pupils at a flag day event was $100. When another 14 pupils turned up to help, the total amount donated increased by $740 and the average amount of money collected became $88. How many pupils were there in the group at first?
|
Number of pupils at first |
Number of pupils in the end |
Number |
1 u |
1 u + 14 |
Value |
100 |
88 |
Total Value |
100 u + 740 |
88 u + 1232 |
Number of pupils at first = 1 u
Total amount collected by the pupils at first
= 1 u x 100
= 100 u
Total amount collected by the pupils in the end
= 88 x (1 u + 14)
= 88 u + 1232
100 u + 740 = 88 u + 1232
100 u - 88 u = 1232 - 740
12 u = 492
1 u = 492 ÷ 12 = 41
Number of pupils at first
= 1 u
= 41
Answer(s): 41