Given :
On the first day of ticket sales the school sold 10 senior tickets and 1 child ticket for a total of $85 .
The school took in $75 on the second day by selling 5 senior citizens tickets and 7 child tickets.
To Find :
The price of a senior ticket and the price of a child ticket.
Solution :
Let, price of senior ticket and child ticket is x and y respectively.
Mathematical equation of condition 1 :
10x + y = 85 ...1)
Mathematical equation of condition 2 :
5x + 7y = 75 ...2)
Solving equation 1 and 2, we get :
2(2) - (1) :
2( 5x + 7y - 75 ) - ( 10x +y - 85 ) = 0
10x + 14y - 150 - 10x - y + 85 = 0
13y = 65
y = 5
10x - 5 = 85
x = 8
Therefore, price of a senior ticket and the price of a child ticket $8 and $5.
Hence, this is the required solution.