Question 671386
x = wins
y = losses
...
x + y = 30
x = y + 12
...
y + 12 + y = 30
2y + 12 = 30
2y = 30 - 12
2y = 18
y = 9 lost
...
x + x - 12 = 30
2x - 12 = 30
2x = 42
x = 21 wins
...
Check
12 more won than lost means wins is greater than losses
12+9 = 21

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