The Twelve Days of Crisp Math – Day 5

Fröhliche Weihnachten! A German joke for the Fifth Day of Crisp Math…

What comes between fear and sex?
Fünf!

Speaking of fifths…

Why was 1/5 sent to a counselor?
Because he was two-tenths.

And speaking of fifths again…

Where there are four mathematicians, you’ll surely find a fifth.