One adult ticket costs £11 and one child ticket costs £8.5
Step-by-step explanation:
Let,
Adult ticket = a
Child ticket = c
According to given statement;
3a+4c=67 Eqn 1
5a+6c=106 Eqn 2
Multiplying Eqn 1 by 5;

Multiplying Eqn 2 by 3;

Subtracting Eqn 4 from Eqn 3

Dividing both sides by 2

Putting c=8.5 in Eqn 1

Dividing both sides by 3;

One adult ticket costs £11 and one child ticket costs £8.5
Keywords: Linear equation, subtraction
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