# When Two Plus Two Equals Five #poem #poetry #math #mathisfun #joke

Two plus two is four.
That’s such a narrow view.
It always works in textbooks
Where reality is skewed.

But in the real world,
Anywhere that counts,
Measurements are iffy;
You’ve problems to surmount.

An error band surrounds
Every measurement you take,
It confuses and it obfuscates
The reckonings you make.

Significant figures
Define accuracy,
Where rounding is an issue
And precision is a key.

So if you measure two-point-four,
Don’t round it down to two
And add it next to two-point-three
And think that you are through.

Two-point-four and two-point-three
Sum to four-point-seven;
You may round that up to five
Without a math transgression.

So now you see that four’s
Not always two plus two;
They sometimes sum to five
For large enough values.

By Kate Rauner

Thanks to one of my favorite sites, straightdope.com, where Cecil recently reminded me of an old math joke: 2 + 2 = 5 for large enough values of 2. Here’s another one:

Mathematicians at a conference take a break at the bar.
“This is a real math town,” says one. “Everyone here knows math.”
“I bet our bartender doesn’t know that the integral of X squared is one third X cubed,” says a second mathematician.
They bet and when the bartender comes over to take their orders, they ask her:
What’s the integral of X squared?
She smiles and says: “One third X cubed plus a constant.”

I haven’t tried to make that one into a poem yet.

All my books, including collections of my science-inspired poetry, are available at Amazon, Barnes & Noble, iTunes, Kobo, and other major online retailers. You’ll also find paperbacks at Create Space and all major digital formats at Smashwords. Read one today.
UPDATE
: 2nd edition of Rhyme and Reason available now – expanded with more new poems ðŸ™‚ at Amazon or your favorite store – all major digital formats.