Betty had four boxes, S, T, U and V which contained a total of 346 apples. She transferred 27 apples from Box S to Box T, 52 apples from Box T to Box U and 73 apples from Box U to Box V. The ratio of the number of apples in Box S to Box T to Box U changed from 3 : 5 : 9 to 1 : 3 : 7. How many apples were in Box V at first?
|
Make p the same (1)x3 = (3) |
S (1) |
T (2) |
U
|
V
|
Before |
9 u |
3 u |
5 u |
9 u |
? |
Change 1 |
- 81 |
- 27 |
+ 27 |
|
|
Change 2 |
|
|
- 52 |
+ 52 |
|
Change 3 |
|
|
|
- 73 |
+ 73 |
After |
3 p |
1 p |
3 p |
7 p |
? |
3 u - 27 = 1 p --- (1)
5 u + 27 - 52 = 3 p
5 u - 25 =
3 p --- (2)
(1)
x 3 9 u - 81 =
3 p --- (3)
Make p the same.
(3) = (2)
9 u - 81 = 5 u - 25
9 u - 5 u = 81 - 25
4 u = 56
1 u = 56 ÷ 4 = 14
Total number of apples in Box S, Box T and Box U
= 3 u + 5 u + 9 u
= 17 u
Total number of apples in Box V at first
= 346 - 17 u
= 346 - 17 x 14
= 346 - 238
= 108
Answer(s): 108