Answer:
$27
Explanation:
Assuming this price list, ...
4 toy cars cost 6 dollars
6 toy cars cost 9 dollars
8 toy cars cost 12 dollars
We recognize that 18 cars is 3 times 6 cars, so the cost will be ...
cost of 18 cars = 3(cost of 6 cars) = 3($9) = $27
The cost of 18 toy cars is $27.