To find the retail price of the trashcan after a 15% markup, you can use the following formula:

$\text{Retail Price} = \text{Cost Price} + (\text{Markup Percentage} \times \text{Cost Price})$

1. Cost Price: $17
2. Markup Percentage: 15% (or 0.15)

Now calculate the markup:

$\text{Markup} = 0.15 \times 17 = 2.55$

Next, add the markup to the cost price:

$\text{Retail Price} = 17 + 2.55 = 19.55$

Therefore, the retail price of the trashcan is $19.55.

Would you like more details or have any questions? Here are some related questions you might consider:

1. How do you calculate the markup percentage if you know the retail price?
2. What would the retail price be if the markup were 20% instead of 15%?
3. How do discounts affect the retail price?
4. What is the profit margin if the trashcan is sold at the retail price?
5. How would you apply a markup to multiple items at different costs?

Tip: Always express the markup percentage as a decimal when performing calculations.