1st Grade Algebra

My youngest daughter made a game to examine the number 29. She's in first grade. It's Sunday.

Her: Write a number sentence that makes 29
Me: 7 x 4 + 1 = 29
Her: Daddy, that's 12
Me: What does that "x" mean?
Her: Oh .. "times"?
Me: Good. What's 7 times 4?
Her: 28
Me: That's great! How did you know that?
Her: Because 29 minus 1 is 28