Jen, Shiyun and Lynn each had some beads and decided to play a game with their beads. In round 1, Jen lost
12 of her beads to Shiyun. In round 2, Shiyun lost
12 of her total number of beads to Lynn. In round 3, Lynn lost
12 of her total number of beads to Jen. In the end, Jen, Shiyun and Lynn had 120, 88 and 55 beads respectively. How many beads did Shiyun have at first?
|
Jen |
Shiyun |
Lynn |
Before 1 |
2 b |
111 |
|
Change 1 |
- 1 b |
+ 1 b |
|
After 1 |
1 b |
176 |
|
Before 2 |
65 |
2 u |
|
Change 2 |
|
- 1 u |
+1 |
After 2 |
|
1 u |
110 |
Before 3 |
|
|
2 p |
Change 3 |
+ 1 p |
|
- 1 p |
After 3 |
|
|
1 p |
Comparing Jen, Shiyun and Lynn in the end |
120 |
88 |
55 |
Working backwards.
1 p = 55
At the start of Round 3:
Number of beads that Lynn had
= 2 p
= 2 x 55
= 110
At the start of Round 2:
Number of beads that Jen had
= 120 - 1 p
= 120 - 55
= 65
At the end of Round 3:
Number of beads that Shiyun had = 88
1 u = 88
At the end of Round 1:
Number of beads that Shiyun had
= 2 u
= 2 x 88
= 176
1 b = 65
At the end of Round 1:
Number of beads that Jen had = 65
At the start of Round 1:
Number of beads that Shiyun had
= 176 - 1 b
= 176 - 65
= 111
Answer(s): 111