Question 1127503
a + c = 1300 
so if we substract the adults what's left is children: 
c = 1300 - a
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1.50a + 0.50c = 1450 
substitute for c:
1.5a + 0.50(1300 - a) = 1450
1.5a + 650 - 0.50a = 1450
1a = 1800
a = 800 this is the number of adults
The children:
1300 - 800 = 500 children
:
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