for educational purposes

It is ok when talking to someone to say 'the universe is estimated to be 14 billion years old'.

Of course that is not true. The universe is estimated to be 13.8 billion years old (even that is merely a rounded up estimation). Yet here in this instance, it is actually better to say 14 billion than to say 13.8 billion years (or any other longer number). A whole number is much easier to remember than a number with a fraction.

For educational purposes, it is better to tell an inaccuracy close to the fact than the fact itself; if it serves drawing a better bigger picture (a sort of initial understanding).

This idea though basic and of great utility has diverse implications.

1) Everyday these 'big picture' bits of information govern every aspect of our lives. We don't know how exactly the oil serves the engine, yet we know we have to change the oil in the car. We don't know how electricity exactly works, yet our entire modern lives are built around it. Similarly with the internet; we have an idea of what it is yet we don't fully understand the technicalities of how it actually works. We understand what a second is, yet we don't truly know why it is that long.

2) This concept of inaccuracy should be used only for the purposes of drawing an initial understanding, a rudimentary beginning. It should not be used if one wishes to become an expert in a particular matter. Or wishes to understand something more deeply.

2.1) Where do we draw the line of what is big picture and what is detail? When can we or can't we be accurate? Is it contingent on the kind of conversation we are having? Is it contingent on who we are having the conversation with? Is it contingent on the platform of which we are sharing this idea?