Kathy had four boxes, W, X, Y and Z which contained a total of 316 pomegranates. She transferred 22 pomegranates from Box W to Box X, 38 pomegranates from Box X to Box Y and 48 pomegranates from Box Y to Box Z. The ratio of the number of pomegranates in Box W to Box X to Box Y changed from 4 : 7 : 10 to 1 : 4 : 7. How many pomegranates were in Box Z at first?
|
Make p the same (1)x4 = (3) |
W (1) |
X (2) |
Y
|
Z
|
Before |
16 u |
4 u |
7 u |
10 u |
? |
Change 1 |
- 88 |
- 22 |
+ 22 |
|
|
Change 2 |
|
|
- 38 |
+ 38 |
|
Change 3 |
|
|
|
- 48 |
+ 48 |
After |
4 p |
1 p |
4 p |
7 p |
? |
4 u - 22 = 1 p --- (1)
7 u + 22 - 38 = 4 p
7 u - 16 =
4 p --- (2)
(1)
x 4 16 u - 88 =
4 p --- (3)
Make p the same.
(3) = (2)
16 u - 88 = 7 u - 16
16 u - 7 u = 88 - 16
9 u = 72
1 u = 72 ÷ 9 = 8
Total number of pomegranates in Box W, Box X and Box Y
= 4 u + 7 u + 10 u
= 21 u
Total number of pomegranates in Box Z at first
= 316 - 21 u
= 316 - 21 x 8
= 316 - 168
= 148
Answer(s): 148