Question

The weather report says there is a 91% chance it will rain tomorrow. Should you get ready to use an umbrella?

Answer 1

Yes
Even if it was 80%, you would still want to bring an umbrella just in case

Answer 2

Maybe. This is because even though it says 91%, the weather changes because of global warming which concludes to there not actually being any exact results but, still take an umbrella just to make sure.

Hope this answer was reasonable for you :)