A note on denominators:
When I was a child, my grandmother used to watch beside me as I played with marbles.
When she passed away, it was the first time I became completely aware - eight billion is the number of times a human heart is said to beat in a lifetime.

If there is a denominator, there is also a limit.

A note on numerators:
Have you ever thought about the number of times since you were born that your heart has beaten without you being conscious of it?
Your heartbeat just this instant has its own meaning and colour and is unrepeatable.
What aspect does the eight billionth of your life at this instant present to you?