The total number of adult tickets sold is 250.
x / y = 2/5
Cross multiply :5x = 2y
y = 5/2
y = 2.5x
(x + 70) / (y + 300) = 1/3
Cross multiply :210 + 3x = 300 + y
Substitute for y
210 + 3x = 300 + 2.5x
300 - 210 = 3x - 2.5x
90 = 0.5x
x = 90 / 0.5
x = 180
Total tickets sold = 180 + 70 = 250
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