Jane, Wendy and Sabrina each had some marbles and decided to play a game with their marbles. In round 1, Jane lost ¹₂ of her marbles to Wendy. In round 2, Wendy lost ¹₂ of her total number of marbles to Sabrina. In round 3, Sabrina lost ¹₂ of her total number of marbles to Jane. In the end, Jane, Wendy and Sabrina had 134, 94 and 61 marbles respectively. How many marbles did Wendy have at first?

	Jane	Wendy	Sabrina
Before  1	2 b	115
Change 1	- 1 b	+ 1 b
After 1	1 b	188
Before 2	73	2 u
Change 2		- 1 u	+1
After 2		1 u	122
Before 3			2 p
Change 3	+ 1 p		- 1 p
After 3			1 p
Comparing Jane, Wendy and Sabrina in the end	134	94	61

Working backwards.

1 p = 61

At the start of Round 3:
Number of marbles that Sabrina had
= 2 p
= 2 x 61 
= 122

At the start of Round 2:
Number of marbles that Jane had
= 134 - 1 p
= 134 - 61
= 73

At the end of Round 3:
Number of marbles that Wendy had = 94

1 u = 94

At the end of Round 1:
Number of marbles that Wendy had
= 2 u
= 2 x 94 
= 188

1 b = 73 

At the end of Round 1:
Number of marbles that Jane had = 73

At the start of Round 1:
Number of marbles that Wendy had
= 188 - 1 b
= 188 - 73
= 115

Answer(s): 115