So I am writing my paper and I am confused I know you use fewer when you have something countable like items. and less when its not a countable things. For my example would I say that 5% concentration of coffee had less of an effect of fewer effects than a 10% concentration of coffee . thanks

Answer 1

I would use "less of an effect" -- unless you have named different effects separately.

Answer 2

Okay, Thanks!

Answer 3

You're welcome.