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.
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.
I don’t think anyone ever counts it like that.
And eyes.
And lungs, and … :-/
The average person contains more than one heart (due to late term pregnant women)
And more than one skeleton.
What is tripping you up exactly? Most statistics are population level averages, so they are divided by a large number.