Please help! I need this quickly!
Devon purchased tickets to an air show for 8 adults and 2 children. The total cost was $166. The cost of a child's ticket was $7 less than the cost of an adult's ticket. Find the price of an adult's ticket and a child's ticket.
A) adults ticket: $19 ; child's ticket: $12
B) adult's ticket: $20; child's ticket: $13
C) adult's ticket: $17; child's ticket: $10
D) adult's ticket: $18; child's ticket: $11