Answer:
see below
Explanation:
519 sold
studnets = x
non students = y
so x+y =519, so x = 519-y
3x+5y =1909
so 3(519-y) +5y = 1557 +2y =1909
2y = 352
y=176 non students
x = 519-176 = 343 students
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