The number of children ticket sold on Sunday is 210.
Given this equations:
x+y=370 equation 1
3x+7y=1750 equation 2
Multiply equation 1 by 7
7x + 7y = 2590 equation 3
Subtract equation 2 from equation 3
4y = 840
Divide both sides by 4
y = 840 / 4
y = 210
To learn more about simultaneous equations, please check: https://brainly.com/question/25875552
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