The mind of a 7 year old

Clayton is in a math enrichment program at school. They meet once a week and bring home a sheet of challenging math questions to work on during the week. He is required to do it on his own (no help from parents) and show his work.
This morning Chris and I were reading one of his questions and wondered how Clayton would show his work on an algebraic question. The question was;

Mrs. Leary has chickens and dogs in her backyard. She counts 15 head and 42 feet. How many dogs does Mrs. Leary have?

This is what Clayton wrote for his answer and show of work;

5 dogs
because 5 dogs and 10 chickens = 40 feet
+ Ms. Learys 2 feet = 42 feet
and she can't count her head because she can't see it.

The teacher can't mark that wrong right? I bet he is the only kid in his class with that answer. I love how is little mind works.

Edit April 9th:

Clayton came home from school very excited to tell me that he got a 100% on his math enrichment home work. I told him how proud I was and said, so you got ALL of them right, that's great! He replied "Yep, and you know that one about the dogs and chickens? I guess there were two answers and I got one of them!"