John had three boxes, containing a total of 880 plastic plates. The number of plastic plates in Box G to the total number of plastic plates was 3 : 11. He sold 332 plastic plates from Box H and sold
13 of the plastic plates in Box J. The number of plastic plates left in Box H to the number of plastic plates left in Box J was 4 : 1. How many plastic plates were there in Box H at first?
|
Box G |
Box H |
Box J |
Total |
Before |
3 u
|
8 u (640)
|
11 u (880) |
|
|
8 p + 332 |
3 p |
|
Change |
|
- 332 |
- 1 p |
|
|
|
|
2 p |
|
After |
|
4x2 = 8 p |
1x2 = 2 p |
|
11 u = 880
1 u = 880 ÷ 11 = 80
Number of plastic plates in Box H and Box J at first
= 8 u
= 8 x 80
= 640
The number of plates left in J is the repeated identity.
LCM of 1 and 2 = 2
8 p + 332 + 3 p = 640
8 p + 3 p = 640 - 332
11 p = 308
1 p = 308 ÷ 11 = 28
Number of plates in Box H at first
= 8 p + 332
= 8 x 28 + 332
= 224 + 332
= 556
Answer(s):556