Final answer:
The cost of a pancake is $4.50.
Step-by-step explanation:
To find the cost of a pancake, we need to set up an equation using the given information. Let's represent the cost of a pancake as 'p'. We know that 8 waffles cost $4 more than 8 pancakes, so we can say that the cost of 8 waffles is 'p + 4'. Additionally, Harry paid $18 for 4 pancakes, so the cost of 1 pancake can be found by dividing $18 by 4: '18/4 = 4.5'. Therefore, the cost of a pancake is $4.50.