bragging

I just took Kenzie's folder out of her backpack and saw that she had math homework. So I read the question to her. It was....

"What's the number: You say the number when you count by 2s. You say the number when you count by 5s. You say the number when you count by 10s. The number is greater than 20 and less than 40. What is the number?"

She is supposed to use numbers and pictures to figure it out. I turned my head and was about to suggest some ways she could figure it out and she said "30". so very matter-o-fact'ly.

She is a smartie-pants.