Kylie, Lynn and Xuan each had some beads and decided to play a game with their beads. In round 1, Kylie lost
13 of her beads to Lynn. In round 2, Lynn lost
13 of her total number of beads to Xuan. In round 3, Xuan lost
13 of her total number of beads to Kylie. In the end, Kylie, Lynn and Xuan had 146, 74 and 80 beads respectively. How many beads did Lynn have at first?
|
Kylie |
Lynn |
Xuan |
|
|
58 |
|
Before 1 |
3 b |
|
|
Change 1 |
- 1 b |
+ 1 b |
|
After 1 |
2 b |
111 |
|
Before 2 |
106 |
3 u |
|
Change 2 |
|
- 1 u |
+ 1 u |
After 2 |
|
2 u |
120 |
Before 3 |
|
|
3 p |
Change 3 |
+ 1 p |
|
- 1 p |
After 3 |
|
|
2 p |
Comparing Kylie, Lynn and Xuan in the end |
146 |
74 |
80 |
Working backwards.
2 p = 80
1 p = 80 ÷ 2 = 40
At the start of Round 3:
Number of beads that Xuan had
= 3 p
= 3 x 40
= 120
2 u = 74
1 u = 74 ÷ 2 = 37
At the start of Round 2:
Number of beads that Lynn had
= 3 u
= 3 x 37
= 111
At the start of Round 2:
Number of beads that Kylie had
= 146 - 40
= 106
2 b = 106
1 b = 106 ÷ 2 = 53
At the start of Round 1:
Number of beads that Lynn had
= 111 - 1 b
= 111 - 53
= 58
Answer(s): 58