To figure out the correct equation representing the cost of ice skating, we can analyze the problem. Giliafh paid $21 in total for 3 hours of skating and $3 for skate rental. This means the skating sessions cost $21 - $3 = $18 for 3 hours. Therefore, the hourly rate can be calculated as $18 / 3 hours = $6 per hour.

Putting it all together, the equation for the total cost for hours of skating would be:

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Real-world applications of this equation can be found at countless ice skating rinks! They often operate similarly, where the overall cost includes rental fees and a charge for the time spent skating. So, the equation helps you plan your skating days without blowing your budget!

Now, let’s talk about a common mistake when working with these equations: confusing the components! A lot of people tend to add the rental fee to the cost per hour correctly but may overlook operational details, like sliding your rental fee into different time buckets. Always break down costs step by step to avoid these blunders!