Owen had three boxes, containing a total of 1000 paper plates. The number of paper plates in Box B to the total number of paper plates was 3 : 10. He sold 457 paper plates from Box C and sold
13 of the paper plates in Box D. The number of paper plates left in Box C to the number of paper plates left in Box D was 3 : 1. How many paper plates were there in Box C at first?
|
Box B |
Box C |
Box D |
Total |
Before |
3 u
|
7 u (700)
|
10 u (1000) |
|
|
6 p + 457 |
3 p |
|
Change |
|
- 457 |
- 1 p |
|
|
|
|
2 p |
|
After |
|
3x2 = 6 p |
1x2 = 2 p |
|
10 u = 1000
1 u = 1000 ÷ 10 = 100
Number of paper plates in Box C and Box D at first
= 7 u
= 7 x 100
= 700
The number of plates left in D is the repeated identity.
LCM of 1 and 2 = 2
6 p + 457 + 3 p = 700
6 p + 3 p = 700 - 457
9 p = 243
1 p = 243 ÷ 9 = 27
Number of plates in Box C at first
= 6 p + 457
= 6 x 27 + 457
= 162 + 457
= 619
Answer(s):619