26 - x = 17

.........................................................................................................

y + 18 = 27

.........................................................................................................

13 + z = 22

.........................................................................................................

24 - a = 15

.........................................................................................................

21 - b = 12

.........................................................................................................

26 - x = 18

.........................................................................................................

y + 19 = 27

..........................................................................................................

23 - z = 15

..........................................................................................................

14 + a = 22

..........................................................................................................

22 - b = 14

..........................................................................................................

25 - x = 19

...........................................................................................................

y + 17 = 23

...........................................................................................................

15 + z = 21

...........................................................................................................

24 - a = 18

...........................................................................................................

21 - b = 15

............................................................................................................

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