Dana, Kimberly and Jean each had some balls and decided to play a game with their balls. In round 1, Dana lost
12 of her balls to Kimberly. In round 2, Kimberly lost
12 of her total number of balls to Jean. In round 3, Jean lost
12 of her total number of balls to Dana. In the end, Dana, Kimberly and Jean had 132, 94 and 63 balls respectively. How many balls did Kimberly have at first?
|
Dana |
Kimberly |
Jean |
Before 1 |
2 b |
119 |
|
Change 1 |
- 1 b |
+ 1 b |
|
After 1 |
1 b |
188 |
|
Before 2 |
69 |
2 u |
|
Change 2 |
|
- 1 u |
+1 |
After 2 |
|
1 u |
126 |
Before 3 |
|
|
2 p |
Change 3 |
+ 1 p |
|
- 1 p |
After 3 |
|
|
1 p |
Comparing Dana, Kimberly and Jean in the end |
132 |
94 |
63 |
Working backwards.
1 p = 63
At the start of Round 3:
Number of balls that Jean had
= 2 p
= 2 x 63
= 126
At the start of Round 2:
Number of balls that Dana had
= 132 - 1 p
= 132 - 63
= 69
At the end of Round 3:
Number of balls that Kimberly had = 94
1 u = 94
At the end of Round 1:
Number of balls that Kimberly had
= 2 u
= 2 x 94
= 188
1 b = 69
At the end of Round 1:
Number of balls that Dana had = 69
At the start of Round 1:
Number of balls that Kimberly had
= 188 - 1 b
= 188 - 69
= 119
Answer(s): 119