EDIT: Thanks for the answers
These things are averages, and the average of integers can be a non-integer. If two women have one child each and a third woman has two children, the average woman has 1.33 children. Is that what you meant?
my fav example is that the average person has ~1 testicle!
My favourite is that the average amount of legs is less than 2. So most people have an above average amount of legs.
And eyes.
And lungs, and … :-/
Depending on the country, I’d now question this. Does the number of leg amputees (dual counts double) outnumber the number of pregnant women at a given time? Legs form fairly early. Therefore, for about 6 months or so, most pregnant women have 4 legs.
The average person contains more than one heart (due to late term pregnant women)
What is tripping you up exactly? Most statistics are population level averages, so they are divided by a large number.