Answer: $5
Step-by-step explanation:
Let the cost of one adult ticket be x and the cost of one child ticket be y , then from the first statement:
[tex]3x + y = 32[/tex]
And from the second statement , we have
[tex]7x + 2y = 73[/tex]
combining the two equations , we have
[tex]3x + y = 32[/tex] ........................... equation 1
[tex]7x + 2y = 73[/tex] ........................... equation 2
Solving the system of linear equation by substitution method , from equation 1 , make y the subject of the formula ,that is
[tex]y = 32 - 3x[/tex] ............................... equation 3
substitute equation 3 into equation 2 , equation 2 then becomes
[tex]7x + 2 ( 32 - 3x )[/tex] = [tex]73[/tex]
[tex]7x + 64 - 6x = 73[/tex]
[tex]x + 64 = 73[/tex][tex]x = 73 - 64[/tex]
[tex]x = 9[/tex]
Substitute [tex]x = 9[/tex] into equation 3 to find the value of y
[tex]y = 32 - 3x[/tex]
[tex]y = 32 - 3(9)[/tex]
[tex]y = 32 - 27[/tex]
[tex]y = 5[/tex]
Therefore : the cost of one child ticket is $5
