Cathy, Jane and Pamela each had some beads and decided to play a game with their beads. In round 1, Cathy lost
12 of her beads to Jane. In round 2, Jane lost
12 of her total number of beads to Pamela. In round 3, Pamela lost
12 of her total number of beads to Cathy. In the end, Cathy, Jane and Pamela had 139, 88 and 50 beads respectively. How many beads did Jane have at first?
|
Cathy |
Jane |
Pamela |
Before 1 |
2 b |
87 |
|
Change 1 |
- 1 b |
+ 1 b |
|
After 1 |
1 b |
176 |
|
Before 2 |
89 |
2 u |
|
Change 2 |
|
- 1 u |
+1 |
After 2 |
|
1 u |
100 |
Before 3 |
|
|
2 p |
Change 3 |
+ 1 p |
|
- 1 p |
After 3 |
|
|
1 p |
Comparing Cathy, Jane and Pamela in the end |
139 |
88 |
50 |
Working backwards.
1 p = 50
At the start of Round 3:
Number of beads that Pamela had
= 2 p
= 2 x 50
= 100
At the start of Round 2:
Number of beads that Cathy had
= 139 - 1 p
= 139 - 50
= 89
At the end of Round 3:
Number of beads that Jane had = 88
1 u = 88
At the end of Round 1:
Number of beads that Jane had
= 2 u
= 2 x 88
= 176
1 b = 89
At the end of Round 1:
Number of beads that Cathy had = 89
At the start of Round 1:
Number of beads that Jane had
= 176 - 1 b
= 176 - 89
= 87
Answer(s): 87