During a charity drive, Primary 5 raised 5 times as much money as Primary 1 on the first week. On the second week, Primary 5 raised another $320 while Primary 1 raised another $556. During the entire charity event, Primary 5 raised 2 times as much as Primary 1. What was the total amount raised by Primary 5?
|
Primary 5 (1) |
Primary 1 (2) |
Make p the same (2) x 2 = (3) |
Before |
5 u |
1 u |
2 u |
Change |
+ 320 |
+ 556 |
+ 1112 |
After |
2 p |
1 p |
2 p |
(1) = (3)
5 u + 320 = 2 u + 1112
5 u - 2 u = 1112 - 320
3 u = 792
1 u = 792 ÷ 3 = 264
From (2)
1 p = 264 + 556 = 820
Total amount raised by Primary 5
= 2 p
= 2 x 820
= $1640
Answer: $1640