2 + 11 – 1 = 12.

Figure 1 demonstrates a “proof with words”!

**Presentation Suggestions:**

Write the letters for two and eleven side by side, then cross out the letters for one as you say them.

**The Math Behind the Fact:**

This short fun fact does not really involve any mathematics, but it is rather amusing. After this see also Proofs Without Words.

**How to Cite this Page:**

Su, Francis E., et al. “Proof with Words.” *Math Fun Facts*. <https://www.math.hmc.edu/funfacts>.

**Fun Fact suggested by: **

Arthur Benjamin