Xandra, Pamela and Barbara each had some beads and decided to play a game with their beads. In round 1, Xandra lost
15 of her beads to Pamela. In round 2, Pamela lost
15 of her total number of beads to Barbara. In round 3, Barbara lost
15 of her total number of beads to Xandra. In the end, Xandra, Pamela and Barbara had 127, 96 and 76 beads respectively. How many beads did Pamela have at first?
|
Xandra |
Pamela |
Barbara |
|
|
93 |
|
Before 1 |
5 b |
|
|
Change 1 |
- 1 b |
+ 1 b |
|
After 1 |
4 b |
120 |
|
Before 2 |
108 |
5 u |
|
Change 2 |
|
- 1 u |
+ 1 u |
After 2 |
|
4 u |
95 |
Before 3 |
|
|
5 p |
Change 3 |
+ 1 p |
|
- 1 p |
After 3 |
|
|
4 p |
Comparing Xandra, Pamela and Barbara in the end |
127 |
96 |
76 |
Working backwards.
4 p = 76
1 p = 76 ÷ 4 = 19
At the start of Round 3:
Number of beads that Barbara had
= 5 p
= 5 x 19
= 95
4 u = 96
1 u = 96 ÷ 4 = 24
At the start of Round 2:
Number of beads that Pamela had
= 5 u
= 5 x 24
= 120
At the start of Round 2:
Number of beads that Xandra had
= 127 - 19
= 108
4 b = 108
1 b = 108 ÷ 4 = 27
At the start of Round 1:
Number of beads that Pamela had
= 120 - 1 b
= 120 - 27
= 93
Answer(s): 93