Question 1204087
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Answer:
{{{system(a+c+s = 589,17.50a+9c+4.50s=4705,a=4c)}}}



Explanation


a = number of adults
c = number of children
s = number of senior citizens
a+c+s represents the total number of people, which of course must match up with the 589 total tickets sold.
This is how the 1st equation is formed.


17.50a = revenue from the adults
9c = revenue from the children
4.50s = revenue from the senior citizens
17.50a+9c+4.50s = total revenue = 4705 dollars
This helps explain how the 2nd equation was formed.


The last equation a = 4c is from the phrasing "<font color=blue>the number of adult tickets sold was four times as many as the number of children tickets sold</font>"
So for example, if c = 10 children attended then there would be a = 4c = 4*10 = 40 adults.


Because a = 4c, we can replace each copy of 'a' with 4c in the 1st and 2nd equations. 
It will mean we go from 3 variables to 2 variables to help reduce things a bit. 
However, I'll leave the answer as 3 equations, as this is likely what your teacher is looking for.
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