Answer: $5
Explanation:
Let the cost of one adult ticket be x and the cost of one child ticket be y , then from the first statement:
And from the second statement , we have
combining the two equations , we have
........................... equation 1
........................... equation 2
Solving the system of linear equation by substitution method , from equation 1 , make y the subject of the formula ,that is
............................... equation 3
substitute equation 3 into equation 2 , equation 2 then becomes
=
Substitute
into equation 3 to find the value of y
Therefore : the cost of one child ticket is $5