To determine a dog's age equivalent to a 3-year-old human based on the common understanding of dog age conversion, it’s important to note that the conversion isn’t linear and varies by breed and size of the dog.
However, a general rule of thumb often used is:
- The first year of a dog's life is roughly equal to 15 human years.
- The second year is about 9 additional human years (totaling 24).
- Each year thereafter is about 5 human years.
Using this method, a 3-year-old human would be considered to be equivalent to a dog that is approximately 15 years old (the first year) + 9 years (the second year) = 24 years old for a general estimate.
If you have specific data from a graph regarding dog age equivalencies, the answer might differ. If you can provide details from that graph, I could give a more precise answer based on that information.